diff --git a/compiler/error.c b/compiler/error.c
index a39b212..1335d4b 100644
--- a/compiler/error.c
+++ b/compiler/error.c
@@ -129,7 +129,8 @@ static ErrorDefinition dkc_error_message_format[] = {
     {"字符字面量中包含了2个以上的字符。"},
     {"类型转换不匹配。"},
     {"函数调用类型不匹配。"},
-    {"返回值类型不匹配."},
+    {"返回值类型不匹配。"},
+    {"表达式的值没有被使用到。"},
     {"dummy"}};
 
 typedef struct
diff --git a/compiler/error.h b/compiler/error.h
index 89853a9..865f99c 100644
--- a/compiler/error.h
+++ b/compiler/error.h
@@ -133,6 +133,7 @@ typedef enum
     TYPE_CAST_MISMATCH_ERR,
     FUNCTION_CALL_TYPE_MISMATCH_ERR,
     RETURN_TYPE_MISMATCH_ERR,
+    EXPR_EVALUATED_BUT_NOT_USED,
     COMPILE_ERROR_COUNT_PLUS_1,
 } CompileError;
 
diff --git a/compiler/fix_tree.c b/compiler/fix_tree.c
index c136a42..f8d758b 100644
--- a/compiler/fix_tree.c
+++ b/compiler/fix_tree.c
@@ -797,6 +797,18 @@ fix_assign_stmt(Block *current_block, Statement *stmt)
     }
 }
 
+static void
+fix_expression_stmt(Block *current_block, Statement *stmt)
+{
+    stmt->u.expr_s = fix_expression(current_block, stmt->u.expr_s);
+    if (stmt->u.expr_s->kind != FUNC_CALL_EXPRESSION)
+    {
+        compile_error(stmt->line_number,
+                      EXPR_EVALUATED_BUT_NOT_USED,
+                      MESSAGE_ARGUMENT_END);
+    }
+}
+
 static void
 fix_statement(Block *current_block, Statement *statement, FuncDefinition *fd)
 {
@@ -814,6 +826,9 @@ fix_statement(Block *current_block, Statement *statement, FuncDefinition *fd)
     case ASSIGN_STATEMENT:
         fix_assign_stmt(current_block, statement);
         break;
+    case EXPRESSION_STATEMENT:
+        fix_expression_stmt(current_block, statement);
+        break;
     default:
         DBG_assert(0, ("bad case. kind..%d\n", statement->kind));
     }