diff --git a/README.md b/README.md
index 415894d..d1e6db8 100644
--- a/README.md
+++ b/README.md
@@ -85,19 +85,18 @@ void* iter_next();                  // 迭代器下一个元素
 // -------------------- 扩展功能 --------------------
 // 元素相关操作
 bool append(const void* obj);        // 追加元素 <push_back> 一般用于list 
-bool delete(const void* obj);       // 删除元素
-// bool remove(const void *obj);     // 删除元素 <同delete>
+// bool remove(const void *obj);        // 删除元素 <暂不使用该命名>
 bool find(const void* obj);          // 查找元素 <返回值，bool/uint32_t/void*待定？>
 bool contains(const void* obj);      // 判断元素是否存在 <返回bool>
-uint32_t count(const void* obj);     // 统计元素个数
+uint32_t count(const void* obj);     // 统计元素obj的个数
 
 // 索引相关操作
 uint32_t index(void *obj);                      // 获取元素索引
 bool insert(uint32_t index, const void* obj);   // 插入元素 <非树>
-bool erase(uint32_t index);                     // 删除元素
+bool delete(uint32_t index, void* obj);         // 删除元素
+// bool erase(uint32_t index);                     // 删除元素<暂时不用该命名>
 bool set(uint32_t index, const void* obj);      // 设置元素
 bool get(uint32_t index, void* obj);            // 获取元素
-
 ```
 
 ## 特点
diff --git a/demo/demo_deque.c b/demo/demo_deque.c
index 64a05b8..9e85bca 100644
--- a/demo/demo_deque.c
+++ b/demo/demo_deque.c
@@ -140,6 +140,7 @@ static void demo_deque_num(void)
         }
     }
 
+#if 0
     printf("----- push_front -----\n");
     for (i = 0; i < len; i++)
     {
@@ -173,6 +174,7 @@ static void demo_deque_num(void)
             printf("\n");
         }
     }
+#endif
 
     deque_free(&deque);
 }
@@ -334,7 +336,6 @@ static void demo_deque_struct(void)
     printf("----- print -----\n");
     deque->print(deque);
     printf("\n");
-#endif
 
     printf("----- get -----\n");
     for (i = 0; i < len; i++)
@@ -346,6 +347,7 @@ static void demo_deque_struct(void)
             printf("\n");
         }
     }
+#endif
 
     deque_free(&deque);
 }
diff --git a/demo/demo_list.c b/demo/demo_list.c
index c1f6ea2..379c621 100644
--- a/demo/demo_list.c
+++ b/demo/demo_list.c
@@ -32,15 +32,15 @@ static void demo_list_num(void)
     printf("\n");
 
     printf("----- pop -----\n");
-    list->pop(list, 9, NULL);
+    list->delete(list, 9, NULL);
     list->print(list);
     printf("\n");
 
-    list->pop(list, 0, NULL);
+    list->delete(list, 0, NULL);
     list->print(list);
     printf("\n");
 
-    list->pop(list, 4, NULL);
+    list->delete(list, 4, NULL);
     list->print(list);
     printf("\n");
 
@@ -129,7 +129,7 @@ static void demo_list_num(void)
     printf("----- pop -----\n");
     for (i = 0; i < len + 1; i++)
     {
-        list->pop(list, 0, &temp);
+        list->pop(list, &temp);
 
         if (list->empty(list))
         {
@@ -167,15 +167,15 @@ static void demo_list_struct(void)
     printf("\n");
 
     printf("----- pop -----\n");
-    list->pop(list, 9, NULL);
+    list->delete(list, 9, NULL);
     list->print(list);
     printf("\n");
 
-    list->pop(list, 0, NULL);
+    list->delete(list, 0, NULL);
     list->print(list);
     printf("\n");
 
-    list->pop(list, 4, NULL);
+    list->delete(list, 4, NULL);
     list->print(list);
     printf("\n");
 
@@ -286,7 +286,7 @@ static void demo_list_struct(void)
     printf("----- pop -----\n");
     for (i = 0; i < len + 1; i++)
     {
-        list->pop(list, 0, &temp);
+        list->pop(list, &temp);
 
         if (list->empty(list))
         {
diff --git a/include/list.h b/include/list.h
index e1334fa..ce43e83 100644
--- a/include/list.h
+++ b/include/list.h
@@ -35,16 +35,18 @@ struct _list
 
     // -------------------- public --------------------
     // kernel
-    bool (*append)(struct _list *self, void *obj);            // Append object to the end of the list.
-    bool (*insert)(struct _list *self, int index, void *obj); // Insert object before index.
-    bool (*pop)(struct _list *self, int index, void *obj);    // Remove and return item at index.
-
-    int (*index)(struct _list *self, void *obj);    // Return first index of obj. Return -1 if the obj is not present.
-    bool (*remove)(struct _list *self, void *obj);  // Remove first occurrence of obj.
+    bool (*append)(struct _list *self, void *obj);
+    bool (*pop)(struct _list *self, void *obj);
+    
+    bool (*insert)(struct _list *self, int index, void *obj);
+    bool (*delete)(struct _list *self, int index, void *obj);
 
     bool (*get)(struct _list *self, int index, void *obj);
     bool (*set)(struct _list *self, int index, void *obj);
 
+    int (*index)(struct _list *self, void *obj);
+    // bool (*contains)(struct _list *self, void *obj);
+
     // base
     uint32_t (*size)(struct _list *self);
     uint32_t (*capacity)(struct _list *self);
@@ -54,16 +56,9 @@ struct _list
     // iter
     iterator_t (*iter)(struct _list *self);
 
-    // sort
-    // bool (*reverse)(struct _list* self);        // Reverse *IN PLACE*.
-    /**
-        Sort the list in ascending order and return false.
-        The sort is in-place (i.e. the list itself is modified) and stable (i.e. the
-        order of two equal elements is maintained).
-        The reverse flag can be set to sort in descending order.
-    */
-    // bool (*sort)(struct _list* self, uint8_t reserve, int (*compare)(void* obj, void* obj2));
-
+    // config
+    compare_fun_t compare;      // !!! you have to implement this function
+    
     // -------------------- debug --------------------
     void (*print)(struct _list *self);
     void (*print_obj)(void *obj);
diff --git a/src/list.c b/src/list.c
index 5bf6b7c..aac1e9d 100644
--- a/src/list.c
+++ b/src/list.c
@@ -35,6 +35,27 @@ static bool list_append(struct _list* self, void* obj)
     return true;
 }
 
+static bool list_pop(struct _list* self, void* obj)
+{
+    assert(self != NULL);
+
+    if (self->empty(self))
+    {
+        return false;
+    }
+
+    uint32_t index = self->size(self) - 1;
+    uint32_t offset = index * self->_obj_size;
+    uint32_t offset_next = (index + 1) * self->_obj_size;
+    if (obj != NULL)
+    {
+        memmove(obj, (char*)self->obj + offset, self->_obj_size);
+    }
+    memmove((char*)self->obj + offset, (char*)self->obj + offset_next, self->_obj_size);
+    self->_size -= 1;
+    return true;
+}
+
 static bool list_insert(struct _list* self, int index, void* obj)
 {
     assert(index >= 0 && index < (int)self->size(self));
@@ -58,7 +79,7 @@ static bool list_insert(struct _list* self, int index, void* obj)
     return true;
 }
 
-static bool list_pop(struct _list* self, int index, void* obj)
+static bool list_delete(struct _list* self, int index, void* obj)
 {
     assert(self != NULL);
     assert(index >= (int)(0 - self->size(self)) && index < (int)self->size(self));
@@ -90,12 +111,6 @@ static int list_index(struct _list* self, void* obj)
     return 0;
 }
 
-static bool list_remove(struct _list* self, void* obj)
-{
-    assert(self != NULL);
-    return true;
-}
-
 static bool list_clear(struct _list* self)
 {
     assert(self != NULL);
@@ -142,16 +157,6 @@ static bool list_empty(struct _list* self)
     return !self->size(self);
 }
 
-static bool list_reverse(struct _list* self)
-{
-    return true;
-}
-
-static bool list_sort(struct _list* self, uint8_t reserve, int (*compare)(void* obj, void* obj2))
-{
-    return true;
-}
-
 // free
 static void list_destory(struct _list* self)
 {
@@ -240,27 +245,25 @@ static bool list_init2(struct _list* list, uint32_t obj_size, uint32_t capacity)
     // -------------------- public -------------------- 
     // kernel
     list->append = list_append;
-    list->insert = list_insert;
     list->pop = list_pop;
 
-    list->empty = list_empty;
+    list->insert = list_insert;
+    list->delete = list_delete;
+
+    list->get = list_get;
+    list->set = list_set;
+
+    list->index = list_index;
+    // list->contains = list_contains;
 
     // base
     list->clear = list_clear;
     list->size = list_size;
+    list->empty = list_empty;
 
     // iter
     list->iter = list_iter;
 
-    // others
-    list->index = list_index;
-    list->remove = list_remove;
-    list->get = list_get;
-    list->set = list_set;
-
-    // list->reverse = list_reverse;
-    // list->sort = list_sort;
-
     // -------------------- debug -------------------- 
     list->print = list_print;
     
diff --git a/test/test_deque.c b/test/test_deque.c
index 58baff5..d5422a6 100644
--- a/test/test_deque.c
+++ b/test/test_deque.c
@@ -113,6 +113,7 @@ static void test_deque_num(void)
         }
     }
 
+#if 0
     for (i = 0; i < len; i++)
     {
         TEST_ASSERT_TRUE(deque->push_front(deque, &data[i]));
@@ -130,6 +131,7 @@ static void test_deque_num(void)
     {
         TEST_ASSERT_TRUE(deque->get(deque, i, &temp));
     }
+#endif
 
     deque_free(&deque);
     TEST_ASSERT_NULL(deque);
@@ -254,10 +256,12 @@ static void test_deque_struct(void)
         TEST_ASSERT_TRUE(deque->push_front(deque, &data[i]));
     }
 
+#if 0
     for (i = 0; i < len; i++)
     {
         TEST_ASSERT_TRUE(deque->get(deque, i, &temp));
     }
+#endif
 
     deque_free(&deque);
     TEST_ASSERT_NULL(deque);
diff --git a/test/test_list.c b/test/test_list.c
index dfcf180..56c5081 100644
--- a/test/test_list.c
+++ b/test/test_list.c
@@ -80,10 +80,10 @@ static void test_list_pop(void)
     }
     for (i = 0; i < len; i++)
     {
-        TEST_ASSERT_TRUE(list->pop(list, 0, &temp));
+        TEST_ASSERT_TRUE(list->pop(list, &temp));
     }
     TEST_ASSERT_TRUE(list->empty(list));
-    // TEST_ASSERT_FALSE(list->pop(list, 1, &temp));
+    TEST_ASSERT_FALSE(list->pop(list, &temp));
     list_free(&list);
 }
 
@@ -129,9 +129,9 @@ static void test_list_num(void)
     {
         TEST_ASSERT_TRUE(list->append(list, &data[i]));
     }
-    TEST_ASSERT_TRUE(list->pop(list, 9, NULL));
-    TEST_ASSERT_TRUE(list->pop(list, 0, NULL));
-    TEST_ASSERT_TRUE(list->pop(list, 4, NULL));
+    TEST_ASSERT_TRUE(list->delete(list, 9, NULL));
+    TEST_ASSERT_TRUE(list->delete(list, 0, NULL));
+    TEST_ASSERT_TRUE(list->delete(list, 4, NULL));
     TEST_ASSERT_TRUE(list->clear(list));
 
     for (i = 0; i < len; i++)
@@ -182,7 +182,7 @@ static void test_list_num(void)
 
     for (i = 0; i < len + 1; i++)
     {
-        TEST_ASSERT_TRUE(list->pop(list, 0, &temp));
+        TEST_ASSERT_TRUE(list->pop(list, &temp));
 
         if (list->empty(list))
         {
@@ -213,9 +213,9 @@ static void test_list_struct(void)
     {
         TEST_ASSERT_TRUE(list->append(list, &data[i]));
     }
-    TEST_ASSERT_TRUE(list->pop(list, 9, NULL));
-    TEST_ASSERT_TRUE(list->pop(list, 0, NULL));
-    TEST_ASSERT_TRUE(list->pop(list, 4, NULL));
+    TEST_ASSERT_TRUE(list->delete(list, 9, NULL));
+    TEST_ASSERT_TRUE(list->delete(list, 0, NULL));
+    TEST_ASSERT_TRUE(list->delete(list, 4, NULL));
 
     TEST_ASSERT_TRUE(list->clear(list));
     for (i = 0; i < len; i++)
@@ -272,7 +272,7 @@ static void test_list_struct(void)
 
     for (i = 0; i < len + 1; i++)
     {
-        TEST_ASSERT_TRUE(list->pop(list, 0, &temp));
+        TEST_ASSERT_TRUE(list->pop(list, &temp));
 
         if (list->empty(list))
         {