keep a rein on

• vt. 约束

keep a rein on的用法和样例：

例句

用作及物动词 (vt.)

1. The rabble must be kept in a short leash.
   对这种下等人必须严加约束。
2. I made a conscious effort to get there on time.
   我刻意约束自己准时到达那里。

词汇搭配

• keep a tight rein on 约束
• keep a slack rein on something 控制不紧