diff --git a/Project/Linux_Posix/mutex/src/main.c b/Project/Linux_Posix/mutex/src/main.c
index 989526b..c02afeb 100644
--- a/Project/Linux_Posix/mutex/src/main.c
+++ b/Project/Linux_Posix/mutex/src/main.c
@@ -25,10 +25,12 @@ void entry_task_1(void *arg)
         if (counter >= MAX_COUNT) {
             tos_task_destroy(K_NULL);
         }
+        // take mutex lock
         err = tos_mutex_pend(&counter_lock);
         if (err == K_ERR_NONE) {
             counter++;
             printf("Task %s: Counter is %d\n", tos_task_curr_task_get() -> name, counter);
+            // give mutex lock
             tos_mutex_post(&counter_lock);
         }
         if (counter > 50) {
@@ -46,10 +48,12 @@ void entry_task_2(void *arg)
         if (counter >= MAX_COUNT) {
             tos_task_destroy(K_NULL);
         }
+        // take mutex lock
         err = tos_mutex_pend(&counter_lock);
         if (err == K_ERR_NONE) {
             counter++;
             printf("Task %s: Counter is %d\n", tos_task_curr_task_get() -> name, counter);
+            // give mutex lock
             tos_mutex_post(&counter_lock);
         }
         tos_task_delay(300);
@@ -59,7 +63,7 @@ void entry_task_2(void *arg)
 int main(void)
 {
     tos_knl_init();
-    // 创建临界区保护互斥锁
+    // create mutex
     tos_mutex_create(&counter_lock);
     (void)tos_task_create(&task_1, "task1", entry_task_1, NULL,
                             4, stack_task_1, STK_SIZE_TASK_1, 0);