diff --git a/balloon/balloon_parse.h b/balloon/balloon_parse.h
index 179848f..4da62d3 100644
--- a/balloon/balloon_parse.h
+++ b/balloon/balloon_parse.h
@@ -69,56 +69,217 @@ class balloon_parse
 		{
 			return error;
 		}
-		void definition();
-		void assignment();
-		void array_generate();
-		void hash_generate();
-		void check_number();
-		void check_string();
-		void check_unary();
-		void block();
-		void func_generate();
-		void call_identifier();
-		void calculation();
-		void calculation_or();
-		void calculation_and();
-		void calculation_cmp();
-		void calculation_additive();
-		void calculation_multive();
-		void scalar();
+		void print_generated_tree()
+		{
+			std::cout<<">>[Abstract-syntax-tree]"<<std::endl;
+			root.print_tree(1);
+			return;
+		}
+		abstract_syntax_tree ret();
+		abstract_syntax_tree choose();
+		abstract_syntax_tree loop();
+		abstract_syntax_tree definition();
+		abstract_syntax_tree assignment();
+		abstract_syntax_tree array_generate();
+		abstract_syntax_tree hash_generate();
+		abstract_syntax_tree check_number();
+		abstract_syntax_tree check_string();
+		abstract_syntax_tree check_unary();
+		abstract_syntax_tree block();
+		abstract_syntax_tree func_generate();
+		abstract_syntax_tree call_identifier();
+		abstract_syntax_tree calculation();
+		abstract_syntax_tree calculation_or();
+		abstract_syntax_tree calculation_and();
+		abstract_syntax_tree calculation_cmp();
+		abstract_syntax_tree calculation_additive();
+		abstract_syntax_tree calculation_multive();
+		abstract_syntax_tree scalar();
 		void check_semi();
 		void parse_main();
 };
 
-void balloon_parse::definition()
+abstract_syntax_tree balloon_parse::ret()
 {
+	abstract_syntax_tree new_node;
+	new_node.set_type(__return);
+	get_token();
+	if(this_token.type!=__return)
+	{
+		++error;
+		std::cout<<">>[Parse-error] line "<<this_token.line<<": must use \'return\' here."<<std::endl;
+		return new_node;
+	}
+	get_token();
+	if(this_token.type==__semi)
+		parse.push(this_token);
+	else
+	{
+		parse.push(this_token);
+		new_node.add_child(scalar());
+	}
+	return new_node;
+}
+
+abstract_syntax_tree balloon_parse::choose()
+{
+	abstract_syntax_tree new_node;
+	abstract_syntax_tree temp;
+	new_node.set_type(__ifelse);
+	temp.set_type(__if);
+	get_token();
+	if(this_token.type!=__if)
+	{
+		++error;
+		std::cout<<">>[Parse-error] line "<<this_token.line<<": must use \'if\' when generating an if-else statement."<<std::endl;
+		return new_node;
+	}
+	get_token();
+	if(this_token.type!=__left_curve)
+	{
+		++error;
+		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \'(\'."<<std::endl;
+		return new_node;
+	}
+	temp.add_child(scalar());
+	get_token();
+	if(this_token.type!=__right_curve)
+	{
+		++error;
+		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \')\'."<<std::endl;
+		return new_node;
+	}
+	temp.add_child(block());
+	new_node.add_child(temp);
+	while(1)
+	{
+		temp.set_clear();
+		get_token();
+		if(this_token.type!=__elsif && this_token.type!=__else)
+			break;
+		if(this_token.type==__else)
+		{
+			get_token();
+			if(this_token.type==__if)// else if
+			{
+				temp.set_type(__elsif);
+				get_token();
+				if(this_token.type!=__left_curve)
+				{
+					++error;
+					std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \'(\'."<<std::endl;
+					return new_node;
+				}
+				temp.add_child(scalar());
+				get_token();
+				if(this_token.type!=__right_curve)
+				{
+					++error;
+					std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \')\'."<<std::endl;
+					return new_node;
+				}
+				temp.add_child(block());
+			}
+			else// real else
+			{
+				temp.set_type(__else);
+				parse.push(this_token);
+				temp.add_child(block());
+				break;
+			}
+			new_node.add_child(temp);
+		}
+		else if(this_token.type==__elsif)
+		{
+			temp.set_type(__elsif);
+			get_token();
+			if(this_token.type!=__left_curve)
+			{
+				++error;
+				std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \'(\'."<<std::endl;
+				return new_node;
+			}
+			temp.add_child(scalar());
+			get_token();
+			if(this_token.type!=__right_curve)
+			{
+				++error;
+				std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \')\'."<<std::endl;
+				return new_node;
+			}
+			temp.add_child(block());
+			new_node.add_child(temp);
+		}
+	}
+	return new_node;
+}
+
+abstract_syntax_tree balloon_parse::loop()
+{
+	abstract_syntax_tree new_node;
+	new_node.set_type(__while);
+	get_token();
+	if(this_token.type!=__while)
+	{
+		++error;
+		std::cout<<">>[Parse-error] line "<<this_token.line<<": must use \'while\' when generating a loop."<<std::endl;
+		return new_node;
+	}
+	get_token();
+	if(this_token.type!=__left_curve)
+	{
+		++error;
+		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \'(\'."<<std::endl;
+		return new_node;
+	}
+	new_node.add_child(scalar());
+	get_token();
+	if(this_token.type!=__right_curve)
+	{
+		++error;
+		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \')\'."<<std::endl;
+		return new_node;
+	}
+	new_node.add_child(block());
+	return new_node;
+}
+
+abstract_syntax_tree balloon_parse::definition()
+{
+	abstract_syntax_tree new_node;
+	abstract_syntax_tree temp;
+	new_node.set_type(__definition);
+	temp.set_type(__id);
 	get_token();
 	if(this_token.type!=__var)
 	{
 		++error;
 		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \'var\' here."<<std::endl;
-		return;
+		return new_node;
 	}
 	get_token();
 	if(this_token.type!=__id)
 	{
 		++error;
 		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect an identifier here."<<std::endl;
-		return;
+		return new_node;
 	}
+	temp.set_name(this_token.str);
+	new_node.add_child(temp);
 	get_token();
 	if(this_token.type!=__equal)
 	{
 		++error;
 		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \'=\' here."<<std::endl;
-		return;
+		return new_node;
 	}
-	scalar();
-	return;
+	new_node.add_child(scalar());
+	return new_node;
 }
 
-void balloon_parse::assignment()
+abstract_syntax_tree balloon_parse::assignment()
 {
+	abstract_syntax_tree new_node;
 	get_token();
 	if(!(this_token.type==__equal || this_token.type==__add_equal
 	|| this_token.type==__sub_equal || this_token.type==__mul_equal
@@ -126,20 +287,23 @@ void balloon_parse::assignment()
 	{
 		++error;
 		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect an operator for assignment here."<<std::endl;
-		return;
+		return new_node;
 	}
-	scalar();
-	return;
+	new_node.set_type(this_token.type);
+	new_node.add_child(scalar());
+	return new_node;
 }
 
-void balloon_parse::array_generate()
+abstract_syntax_tree balloon_parse::array_generate()
 {
+	abstract_syntax_tree new_node;
+	new_node.set_type(__array);
 	get_token();
 	if(this_token.type!=__left_bracket)
 	{
 		++error;
 		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \'[\' here."<<std::endl;
-		return;
+		return new_node;
 	}
 	get_token();
 	if(this_token.type!=__right_bracket)
@@ -157,12 +321,12 @@ void balloon_parse::array_generate()
 			case __sub_operator:
 			case __number:
 			case __string:
-			case __id:parse.push(this_token);scalar();break;
+			case __id:parse.push(this_token);new_node.add_child(scalar());break;
 			case __right_bracket:parse.push(this_token);break;
 			default:
 				++error;
 				std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a scalar or \']\' here."<<std::endl;
-				return;
+				return new_node;
 				break;
 		}
 		get_token();
@@ -170,39 +334,45 @@ void balloon_parse::array_generate()
 		{
 			++error;
 			std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \',\' or \']\' here."<<std::endl;
-			return;
+			return new_node;
 		}
 	}
-	return;
+	return new_node;
 }
 
-void balloon_parse::hash_generate()
+abstract_syntax_tree balloon_parse::hash_generate()
 {
+	abstract_syntax_tree new_node;
+	abstract_syntax_tree temp;
+	new_node.set_type(__hash);
 	get_token();
 	if(this_token.type!=__left_brace)
 	{
 		++error;
 		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \'{\' here."<<std::endl;
-		return;
+		return new_node;
 	}
 	get_token();
 	if(this_token.type!=__right_brace)
 		parse.push(this_token);
 	while(this_token.type!=__right_brace)
 	{
+		temp.set_clear();
+		temp.set_type(__id);
 		get_token();
 		if(this_token.type!=__id)
 		{
 			++error;
 			std::cout<<">>[Parse-error] line "<<this_token.line<<": expect an identifier here."<<std::endl;
-			return;
+			return new_node;
 		}
+		temp.set_name(this_token.str);
 		get_token();
 		if(this_token.type!=__colon)
 		{
 			++error;
 			std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \':\' here."<<std::endl;
-			return;
+			return new_node;
 		}
 		get_token();
 		switch(this_token.type)
@@ -215,102 +385,147 @@ void balloon_parse::hash_generate()
 			case __sub_operator:
 			case __number:
 			case __string:
-			case __id:parse.push(this_token);scalar();break;
+			case __id:parse.push(this_token);temp.add_child(scalar());break;
 			case __right_brace:parse.push(this_token);break;
 			default:
 				++error;
 				std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a scalar or \'}\' here."<<std::endl;
-				return;
+				return new_node;
 				break;
 		}
+		new_node.add_child(temp);
 		get_token();
 		if(this_token.type!=__comma && this_token.type!=__right_brace)
 		{
 			++error;
 			std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \',\' or \'}\' here."<<std::endl;
-			return;
+			return new_node;
 		}
 	}
-	return;
+	return new_node;
 }
 
-void balloon_parse::check_number()
+abstract_syntax_tree balloon_parse::check_number()
 {
+	abstract_syntax_tree new_node;
+	new_node.set_type(__number);
 	get_token();
 	if(this_token.type!=__number)
 	{
 		++error;
 		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a number here."<<std::endl;
+		return new_node;
 	}
-	return;
+	new_node.set_number(this_token.str);
+	return new_node;
 }
 
-void balloon_parse::check_string()
+abstract_syntax_tree balloon_parse::check_string()
 {
+	abstract_syntax_tree new_node;
+	new_node.set_type(__string);
 	get_token();
 	if(this_token.type!=__string)
 	{
 		++error;
 		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a string here."<<std::endl;
+		return new_node;
 	}
-	return;
+	new_node.set_string(this_token.str);
+	return new_node;
 }
 
-void balloon_parse::check_unary()
+abstract_syntax_tree balloon_parse::check_unary()
 {
+	abstract_syntax_tree new_node;
 	get_token();
 	if(this_token.type!=__nor_operator && this_token.type!=__sub_operator)
 	{
 		++error;
 		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a unary operator here."<<std::endl;
+		return new_node;
 	}
+	new_node.set_type(this_token.type);
 	get_token();
 	switch(this_token.type)
 	{
-		case __number:parse.push(this_token);check_number();break;
-		case __string:parse.push(this_token);check_string();break;
-		case __id:parse.push(this_token);call_identifier();break;
-		case __left_curve:parse.push(this_token);scalar();break;
-		case __nor_operator:parse.push(this_token);check_unary();break;
+		case __number:parse.push(this_token);new_node.add_child(check_number());break;
+		case __string:parse.push(this_token);new_node.add_child(check_string());break;
+		case __id:parse.push(this_token);new_node.add_child(call_identifier());break;
+		case __left_curve:parse.push(this_token);new_node.add_child(scalar());break;
+		case __nor_operator:parse.push(this_token);new_node.add_child(check_unary());break;
 		default:++error;std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a scalar here."<<std::endl;break;
 	}
-	return;
+	return new_node;
 }
 
-void balloon_parse::block()
+abstract_syntax_tree balloon_parse::block()
 {
+	abstract_syntax_tree new_node;
+	abstract_syntax_tree temp;
+	new_node.set_type(__block);
 	get_token();
 	if(this_token.type!=__left_brace)
 	{
 		++error;
 		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \'{\' ."<<std::endl;
-		return;
+		return new_node;
 	}
 	while(this_token.type!=__right_brace)
 	{
 		get_token();
 		switch(this_token.type)
 		{
+			case __var:parse.push(this_token);new_node.add_child(definition());check_semi();break;
+			case __left_curve:
+			case __left_bracket:
+			case __left_brace:
+			case __nor_operator:
+			case __sub_operator:
+			case __number:
+			case __string:
+			case __id:parse.push(this_token);new_node.add_child(scalar());check_semi();break;
+			case __if:parse.push(this_token);new_node.add_child(choose());break;
+			case __for:
+			case __forindex:
+			case __foreach:
+			case __while:parse.push(this_token);new_node.add_child(loop());break;
+			case __semi:break;
 			case __continue:
-			case __break:check_semi();break;
+			case __break:temp.set_clear();temp.set_type(this_token.type);new_node.add_child(temp);check_semi();break;
+			case __return:parse.push(this_token);new_node.add_child(ret());check_semi();break;
 			case __right_brace:break;
+			default:
+				++error;
+				std::cout<<">>[Parse-error] line "<<this_token.line<<": \'";
+				print_detail_token(this_token.type);
+				std::cout<<"\' should not appear in this scope."<<std::endl;
+				break;
 		}
 	}
-	return;
+	return new_node;
 }
 
-void balloon_parse::func_generate()
+abstract_syntax_tree balloon_parse::func_generate()
 {
+	abstract_syntax_tree new_node;
+	abstract_syntax_tree para;
+	abstract_syntax_tree temp;
+	new_node.set_type(__function);
+	para.set_type(__parameter);
 	get_token();
 	if(this_token.type!=__func)
 	{
 		++error;
 		std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \'func\' here."<<std::endl;
-		return;
+		return new_node;
 	}
 	get_token();
 	if(this_token.type==__left_curve)
 	{
+		get_token();
+		if(this_token.type!=__right_curve)
+			parse.push(this_token);
 		while(this_token.type!=__right_curve)
 		{
 			get_token();
@@ -318,8 +533,12 @@ void balloon_parse::func_generate()
 			{
 				++error;
 				std::cout<<">>[Parse-error] line "<<this_token.line<<": expect identifier when declaring a new function."<<std::endl;
-				return;
+				return new_node;
 			}
+			temp.set_clear();
+			temp.set_type(this_token.type);
+			temp.set_name(this_token.str);
+			para.add_child(temp);
 			if(this_token.type==__dynamic_id)
 			{
 				get_token();
@@ -327,7 +546,7 @@ void balloon_parse::func_generate()
 				{
 					++error;
 					std::cout<<">>[Parse-error] line "<<this_token.line<<": dynamic identifier should have \')\' behind it ."<<std::endl;
-					return;
+					return new_node;
 				}
 			}
 			else
@@ -337,56 +556,75 @@ void balloon_parse::func_generate()
 				{
 					++error;
 					std::cout<<">>[Parse-error] line "<<this_token.line<<": expect \',\' or \')\' here."<<std::endl;	
-					return;
+					return new_node;
 				}
 			}
 		}
 	}
 	else
 		parse.push(this_token);
-	block();
-	return;
+	new_node.add_child(para);
+	new_node.add_child(block());
+	return new_node;
 }
 
-void balloon_parse::call_identifier()
+abstract_syntax_tree balloon_parse::call_identifier()
 {
+	abstract_syntax_tree new_node;
+	abstract_syntax_tree temp;
 	get_token();
 	if(this_token.type!=__id)
 	{
 		++error;
 		std::cout<<">>[Parse-error] line "<<this_token.line<<": must have an identifier here."<<std::endl;
-		return;
+		return new_node;
 	}
+	new_node.set_type(__id);
+	new_node.set_name(this_token.str);
 	while(1)
 	{
 		get_token();
 		if(this_token.type==__left_curve)
 		{
+			temp.set_clear();
+			temp.set_type(__call_function);
+			get_token();
+			if(this_token.type!=__right_curve)
+				parse.push(this_token);
 			while(this_token.type!=__right_curve)
 			{
-				scalar();
+				temp.add_child(scalar());
 				get_token();
 				if(this_token.type!=__comma && this_token.type!=__right_curve)
 				{
 					++error;
 					std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \',\' or \')\' here."<<std::endl;
-					return;
+					return new_node;
 				}
 			}
+			new_node.add_child(temp);
 		}
 		else if(this_token.type==__left_bracket)
 		{
-			scalar();
+			temp.set_clear();
+			temp.set_type(__call_array);
+			temp.add_child(scalar());
 			get_token();
 			if(this_token.type!=__right_bracket)
 			{
 				++error;
 				std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \']\' ."<<std::endl;
-				return;
+				return new_node;
 			}
+			new_node.add_child(temp);
 		}
 		else if(this_token.type==__dot)
-			call_identifier();
+		{
+			temp.set_clear();
+			temp=call_identifier();
+			temp.set_type(__call_hash);
+			new_node.add_child(temp);
+		}
 		else
 		{
 			parse.push(this_token);
@@ -399,54 +637,102 @@ void balloon_parse::call_identifier()
 	|| this_token.type==__div_equal || this_token.type==__link_equal)
 	{
 		parse.push(this_token);
-		assignment();
+		temp=new_node;
+		new_node=assignment();
+		new_node.add_child(temp);
 	}
 	else
 		parse.push(this_token);
-	return;
+	return new_node;
 }
 
-void balloon_parse::calculation()
+abstract_syntax_tree balloon_parse::calculation()
 {
-	calculation_or();
-	return;
+	abstract_syntax_tree new_node;
+	new_node=calculation_or();
+	return new_node;
 }
 
-void balloon_parse::calculation_or()
+abstract_syntax_tree balloon_parse::calculation_or()
 {
+	abstract_syntax_tree new_node;
+	abstract_syntax_tree temp;
+	new_node=calculation_and();
+	get_token();
+	if(this_token.type!=__or_operator)
+	{
+		parse.push(this_token);
+		return new_node;
+	}
+	temp.set_type(__or_operator);
+	temp.add_child(new_node);
 	while(1)
 	{
-		calculation_and();
+		temp.add_child(calculation_and());
+		new_node=temp;
+		temp.set_clear();
 		get_token();
 		if(this_token.type!=__or_operator)
 		{
 			parse.push(this_token);
 			break;
 		}
+		temp.set_type(__or_operator);
+		temp.add_child(new_node);
 	}
-	return;
+	return new_node;
 }
 
-void balloon_parse::calculation_and()
+abstract_syntax_tree balloon_parse::calculation_and()
 {
+	abstract_syntax_tree new_node;
+	abstract_syntax_tree temp;
+	new_node=calculation_cmp();
+	get_token();
+	if(this_token.type!=__and_operator)
+	{
+		parse.push(this_token);
+		return new_node;
+	}
+	temp.set_type(__and_operator);
+	temp.add_child(new_node);
 	while(1)
 	{
-		calculation_cmp();
+		temp.add_child(calculation_cmp());
+		new_node=temp;
+		temp.set_clear();
 		get_token();
 		if(this_token.type!=__and_operator)
 		{
 			parse.push(this_token);
 			break;
 		}
+		temp.set_type(__and_operator);
+		temp.add_child(new_node);
 	}
-	return;
+	return new_node;
 }
 
-void balloon_parse::calculation_cmp()
+abstract_syntax_tree balloon_parse::calculation_cmp()
 {
+	abstract_syntax_tree new_node;
+	abstract_syntax_tree temp;
+	new_node=calculation_additive();
+	get_token();
+	if(this_token.type!=__cmp_equal && this_token.type!=__cmp_not_equal
+		&& this_token.type!=__cmp_less && this_token.type!=__cmp_less_or_equal
+		&& this_token.type!=__cmp_more && this_token.type!=__cmp_more_or_equal)
+	{
+		parse.push(this_token);
+		return new_node;
+	}
+	temp.set_type(this_token.type);
+	temp.add_child(new_node);
 	while(1)
 	{
-		calculation_additive();
+		temp.add_child(calculation_additive());
+		new_node=temp;
+		temp.set_clear();
 		get_token();
 		if(this_token.type!=__cmp_equal && this_token.type!=__cmp_not_equal
 		&& this_token.type!=__cmp_less && this_token.type!=__cmp_less_or_equal
@@ -455,82 +741,138 @@ void balloon_parse::calculation_cmp()
 			parse.push(this_token);
 			break;
 		}
+		temp.set_type(this_token.type);
+		temp.add_child(new_node);
 	}
+	return new_node;
 }
 
-void balloon_parse::calculation_additive()
+abstract_syntax_tree balloon_parse::calculation_additive()
 {
+	abstract_syntax_tree new_node;
+	abstract_syntax_tree temp;
+	new_node=calculation_multive();
+	get_token();
+	if(this_token.type!=__add_operator && this_token.type!=__sub_operator && this_token.type!=__link_operator)
+	{
+		parse.push(this_token);
+		return new_node;
+	}
+	temp.set_type(this_token.type);
+	temp.add_child(new_node);
 	while(1)
 	{
-		calculation_multive();
+		temp.add_child(calculation_multive());
+		new_node=temp;
+		temp.set_clear();
 		get_token();
 		if(this_token.type!=__add_operator && this_token.type!=__sub_operator && this_token.type!=__link_operator)
 		{
 			parse.push(this_token);
 			break;
 		}
+		temp.set_type(this_token.type);
+		temp.add_child(new_node);
 	}
-	return;
+	return new_node;
 }
 
-void balloon_parse::calculation_multive()
+abstract_syntax_tree balloon_parse::calculation_multive()
 {
+	abstract_syntax_tree new_node;
+	abstract_syntax_tree temp;
+	get_token();
+	switch(this_token.type)
+	{
+		case __left_curve:
+			new_node=scalar();get_token();
+			if(this_token.type!=__right_curve)
+			{
+				++error;
+				std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \')\' here."<<std::endl;
+				return new_node;
+			}
+			break;
+		case __number:parse.push(this_token);new_node=check_number();break;
+		case __string:parse.push(this_token);new_node=check_string();break;
+		case __id:parse.push(this_token);new_node=call_identifier();break;
+		case __nor_operator:
+		case __sub_operator:parse.push(this_token);new_node=check_unary();break;
+		default:
+			++error;
+			std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a scalar here."<<std::endl;
+			return new_node;
+			break;
+	}
+	get_token();
+	if(this_token.type!=__mul_operator && this_token.type!=__div_operator)
+	{
+		parse.push(this_token);
+		return new_node;
+	}
+	temp.set_type(this_token.type);
+	temp.add_child(new_node);
 	while(1)
 	{
 		get_token();
 		switch(this_token.type)
 		{
 			case __left_curve:
-				scalar();get_token();
+				temp.add_child(scalar());get_token();
 				if(this_token.type!=__right_curve)
 				{
 					++error;
 					std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a \')\' here."<<std::endl;
-					return;
+					return new_node;
 				}
 				break;
-			case __number:parse.push(this_token);check_number();break;
-			case __string:parse.push(this_token);check_string();break;
-			case __id:parse.push(this_token);call_identifier();break;
+			case __number:parse.push(this_token);temp.add_child(check_number());break;
+			case __string:parse.push(this_token);temp.add_child(check_string());break;
+			case __id:parse.push(this_token);temp.add_child(call_identifier());break;
 			case __nor_operator:
-			case __sub_operator:parse.push(this_token);check_unary();break;
+			case __sub_operator:parse.push(this_token);temp.add_child(check_unary());break;
 			default:
 				++error;
 				std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a scalar here."<<std::endl;
-				return;
+				return new_node;
 				break;
 		}
+		new_node=temp;
+		temp.set_clear();
 		get_token();
 		if(this_token.type!=__mul_operator && this_token.type!=__div_operator)
 		{
 			parse.push(this_token);
 			break;
 		}
+		temp.set_type(this_token.type);
+		temp.add_child(new_node);
 	}
-	return;
+	return new_node;
 }
 
-void balloon_parse::scalar()
+abstract_syntax_tree balloon_parse::scalar()
 {
+	abstract_syntax_tree new_node;
 	get_token();
 	switch(this_token.type)
 	{
-		case __func:parse.push(this_token);func_generate();break;
-		case __left_bracket:parse.push(this_token);array_generate();break;
-		case __left_brace:parse.push(this_token);hash_generate();break;
+		case __func:parse.push(this_token);new_node=func_generate();break;
+		case __left_bracket:parse.push(this_token);new_node=array_generate();break;
+		case __left_brace:parse.push(this_token);new_node=hash_generate();break;
 		case __left_curve:
 		case __nor_operator:
 		case __sub_operator:
 		case __number:
 		case __string:
-		case __id:parse.push(this_token);calculation();break;
+		case __id:parse.push(this_token);new_node=calculation();break;
 		default:
 			++error;
 			std::cout<<">>[Parse-error] line "<<this_token.line<<": expect a scalar at this place."<<std::endl;
 			parse.push(this_token);
 			break;
 	}
-	return;
+	return new_node;
 }
 
 void balloon_parse::check_semi()
@@ -546,6 +888,7 @@ void balloon_parse::check_semi()
 
 void balloon_parse::parse_main()
 {
+	root.set_clear();
 	root.set_type(__root);
 	error=0;
 	warning=0;
@@ -555,7 +898,7 @@ void balloon_parse::parse_main()
 		get_token();
 		switch(this_token.type)
 		{
-			case __var:parse.push(this_token);definition();check_semi();break;
+			case __var:parse.push(this_token);root.add_child(definition());check_semi();break;
 			case __left_curve:
 			case __left_bracket:
 			case __left_brace:
@@ -563,9 +906,12 @@ void balloon_parse::parse_main()
 			case __sub_operator:
 			case __number:
 			case __string:
-			case __id:parse.push(this_token);scalar();check_semi();break;
-			case __if:parse.push(this_token);break;
-			case __while:parse.push(this_token);break;
+			case __id:parse.push(this_token);root.add_child(scalar());check_semi();break;
+			case __if:parse.push(this_token);root.add_child(choose());break;
+			case __for:
+			case __forindex:
+			case __foreach:
+			case __while:parse.push(this_token);root.add_child(loop());break;
 			case __semi:break;
 			default:
 				++error;
diff --git a/balloon/balloon_type.h b/balloon/balloon_type.h
index d95aece..446c473 100644
--- a/balloon/balloon_type.h
+++ b/balloon/balloon_type.h
@@ -51,10 +51,14 @@ enum parse_type
 	//basic elements
 	
 	__null_node,
+	__block,
+	__array,
+	__hash,
 	__root,
 	__loop,
 	__ifelse,
 	__function,
+	__parameter,
 	__definition,
 	__assignment,
 	__call_array,
@@ -115,10 +119,14 @@ void print_detail_token(int type)
 		case __string:            context="str";break;
 		
 		case __null_node:         context="null node";break;
+		case __block:             context="block";break;
+		case __array:             context="array";break;
+		case __hash:              context="hash";break;
 		case __root:              context="root";break;
 		case __loop:              context="loop";break;
 		case __ifelse:            context="if-else";break;
 		case __function:          context="function";break;
+		case __parameter:         context="parameter";break;
 		case __definition:        context="definition";break;
 		case __assignment:        context="assignment";break;
 		case __call_array:        context="call array";break;
diff --git a/balloon/main.cpp b/balloon/main.cpp
index 24389ec..6ce9a40 100644
--- a/balloon/main.cpp
+++ b/balloon/main.cpp
@@ -67,6 +67,10 @@ int main()
 			{
 				pas.get_detail_token_stream(lex.get_detail_token());
 				pas.parse_main();
+				if(!pas.get_error())
+					pas.print_generated_tree();
+				else
+					std::cout<<">>[Parse] error(s) found,stop."<<std::endl;
 			}
 			else
 				std::cout<<">>[Lexer] error(s) found,stop."<<std::endl;