diff --git a/version3.0/lib.nas b/version3.0/lib.nas
index 8380568..1c362db 100644
--- a/version3.0/lib.nas
+++ b/version3.0/lib.nas
@@ -59,6 +59,23 @@ var size=func(object)
 {
     return nasal_call_builtin_size(object);
 }
+var contains=func(hash,key)
+{
+    return nasal_call_builtin_contains(hash,key);
+}
+var delete=func(hash,key)
+{
+    nasal_call_builtin_delete(hash,key);
+    return;
+}
+var keys=func(hash)
+{
+    return nasal_call_builtin_get_keys(hash);
+}
+var time=func(begin_time)
+{
+    return nasal_call_builtin_time(begin_time);
+}
 
 var io=
 {
@@ -130,8 +147,3 @@ var math=
         return nasal_call_builtin_cpp_atan2(x,y);
     },
 };
-
-var time=func(begin_time)
-{
-    return nasal_call_builtin_time(begin_time);
-}
\ No newline at end of file
diff --git a/version3.0/nasal_builtin.h b/version3.0/nasal_builtin.h
index ae3a36b..0fd20b4 100644
--- a/version3.0/nasal_builtin.h
+++ b/version3.0/nasal_builtin.h
@@ -2,6 +2,7 @@
 #define __NASAL_BUILTIN_H__
 
 #define in_builtin_find(value_name_string) (local_scope_addr>=0?nasal_vm.gc_get(local_scope_addr).get_closure().get_value_address(value_name_string):-1)
+#define in_builtin_check(value_addr,value_type) (nasal_vm.gc_get(value_addr).get_type()==(value_type))
 
 int nasal_runtime::builtin_print(int local_scope_addr)
 {
@@ -681,4 +682,62 @@ int nasal_runtime::builtin_time(int local_scope_addr)
     nasal_vm.gc_get(ret_addr).set_number((double)time(&begin_time));
     return ret_addr;
 }
+int nasal_runtime::builtin_contains(int local_scope_addr)
+{
+    int hash_addr=in_builtin_find("hash");
+    int key_addr=in_builtin_find("key");
+    if(hash_addr<0 || !in_builtin_check(hash_addr,vm_hash))
+    {
+        std::cout<<">> [runtime] builtin_contains: cannot find value named \'hash\' or wrong type(must be hash)."<<std::endl;
+        ++error;
+        return -1;
+    }
+    if(key_addr<0 || !in_builtin_check(key_addr,vm_string))
+    {
+        std::cout<<">> [runtime] builtin_contains: cannot find value named \'key\' or wrong type(must be string)."<<std::endl;
+        ++error;
+        return -1;
+    }
+    std::string key=nasal_vm.gc_get(key_addr).get_string();
+    bool contains=nasal_vm.gc_get(hash_addr).get_hash().check_contain(key);
+    int ret_addr=nasal_vm.gc_alloc();
+    nasal_vm.gc_get(ret_addr).set_type(vm_number);
+    nasal_vm.gc_get(ret_addr).set_number((double)contains);
+    return ret_addr;
+}
+int nasal_runtime::builtin_delete(int local_scope_addr)
+{
+    int hash_addr=in_builtin_find("hash");
+    int key_addr=in_builtin_find("key");
+    if(hash_addr<0 || !in_builtin_check(hash_addr,vm_hash))
+    {
+        std::cout<<">> [runtime] builtin_delete: cannot find value named \'hash\' or wrong type(must be hash)."<<std::endl;
+        ++error;
+        return -1;
+    }
+    if(key_addr<0 || !in_builtin_check(key_addr,vm_string))
+    {
+        std::cout<<">> [runtime] builtin_delete: cannot find value named \'key\' or wrong type(must be string)."<<std::endl;
+        ++error;
+        return -1;
+    }
+    std::string key=nasal_vm.gc_get(key_addr).get_string();
+    nasal_vm.gc_get(hash_addr).get_hash().del_elem(key);
+    int ret_addr=nasal_vm.gc_alloc();
+    nasal_vm.gc_get(ret_addr).set_type(vm_nil);
+    return ret_addr;
+}
+int nasal_runtime::builtin_getkeys(int local_scope_addr)
+{
+    int hash_addr=in_builtin_find("hash");
+    if(hash_addr<0 || !in_builtin_check(hash_addr,vm_hash))
+    {
+        std::cout<<">> [runtime] builtin_delete: cannot find value named \'hash\' or wrong type(must be hash)."<<std::endl;
+        ++error;
+        return -1;
+    }
+
+    int ret_addr=nasal_vm.gc_get(hash_addr).get_hash().get_keys();
+    return ret_addr;
+}
 #endif
\ No newline at end of file
diff --git a/version3.0/nasal_gc.h b/version3.0/nasal_gc.h
index bb0ab83..1b0007c 100644
--- a/version3.0/nasal_gc.h
+++ b/version3.0/nasal_gc.h
@@ -40,6 +40,8 @@ public:
     int  size();
     int  get_value_address(std::string);
     int  get_mem_address(std::string);
+    bool check_contain(std::string);
+    int get_keys();
 };
 
 class nasal_function
@@ -248,8 +250,6 @@ void nasal_hash::add_elem(std::string key,int value_address)
         nasal_vm.mem_init(memory_address,value_address);
         elems[key]=memory_address;
     }
-    else
-        std::cout<<">> [vm] nasal_hash::add_elem: "<<key<<" already exists."<<std::endl;
     return;
 }
 void nasal_hash::del_elem(std::string key)
@@ -259,8 +259,6 @@ void nasal_hash::del_elem(std::string key)
         nasal_vm.mem_free(elems[key]);
         elems.erase(key);
     }
-    else
-        std::cout<<">> [vm] nasal_hash::del_elem: "<<key<<" does not exist."<<std::endl;
     return;
 }
 int nasal_hash::size()
@@ -317,6 +315,46 @@ int nasal_hash::get_mem_address(std::string key)
     }
     return ret_mem_addr;
 }
+bool nasal_hash::check_contain(std::string key)
+{
+    if(elems.find(key)!=elems.end())
+        return true;
+    if(elems.find("parents")!=elems.end())
+    {
+        bool result=false;
+        int mem_addr=elems["parents"];
+        int val_addr=nasal_vm.mem_get(mem_addr);
+        if(nasal_vm.gc_get(val_addr).get_type()==vm_vector)
+        {
+            nasal_vector& vec_ref=nasal_vm.gc_get(val_addr).get_vector();
+            int size=vec_ref.size();
+            for(int i=0;i<size;++i)
+            {
+                int tmp_val_addr=vec_ref.get_value_address(i);
+                if(nasal_vm.gc_get(tmp_val_addr).get_type()==vm_hash)
+                    result=nasal_vm.gc_get(tmp_val_addr).get_hash().check_contain(key);
+                if(result)
+                    break;
+            }
+        }
+        return result;
+    }
+    return false;
+}
+int nasal_hash::get_keys()
+{
+    int ret_addr=nasal_vm.gc_alloc();
+    nasal_vm.gc_get(ret_addr).set_type(vm_vector);
+    nasal_vector& ref_vec=nasal_vm.gc_get(ret_addr).get_vector();
+    for(std::map<std::string,int>::iterator iter=elems.begin();iter!=elems.end();++iter)
+    {
+        int str_addr=nasal_vm.gc_alloc();
+        nasal_vm.gc_get(str_addr).set_type(vm_string);
+        nasal_vm.gc_get(str_addr).set_string(iter->first);
+        ref_vec.add_elem(str_addr);
+    }
+    return ret_addr;
+}
 
 /*functions of nasal_function*/
 nasal_function::nasal_function()
diff --git a/version3.0/nasal_runtime.h b/version3.0/nasal_runtime.h
index 3fb7f91..5dac346 100644
--- a/version3.0/nasal_runtime.h
+++ b/version3.0/nasal_runtime.h
@@ -96,6 +96,9 @@ private:
     int builtin_sqrt(int);
     int builtin_atan2(int);
     int builtin_time(int);
+    int builtin_contains(int);
+    int builtin_delete(int);
+    int builtin_getkeys(int);
     void load_builtin_function();
 public:
     nasal_runtime();
@@ -157,6 +160,9 @@ void nasal_runtime::load_builtin_function()
         {"nasal_call_builtin_cpp_math_sqrt", nasal_runtime::builtin_sqrt},
         {"nasal_call_builtin_cpp_atan2",     nasal_runtime::builtin_atan2},
         {"nasal_call_builtin_time",          nasal_runtime::builtin_time},
+        {"nasal_call_builtin_contains",      nasal_runtime::builtin_contains},
+        {"nasal_call_builtin_delete",        nasal_runtime::builtin_delete},
+        {"nasal_call_builtin_get_keys",      nasal_runtime::builtin_getkeys},
         {"",                                 NULL}
     };
     for(int i=0;builtin_func_table[i].func_pointer;++i)