tightens
['taitn]
[ tightens ]
vt.使紧, 勒紧, 固定
vi.变紧
例句与用法：
He tightened his grip on her arm.
他紧抓她的手臂。
Controls in the city have gradually tightened.
对这个城市的控制逐渐加强。
This screw needs tightening.
这螺丝钉需要再拧紧些。
词形变化：
名词: tightener | 动词过去式: tightened | 动词过去分词: tightened | 动词现在分词: tightening | 动词第三人称单数: tightens |