thumb latch

例句：

1. 1. The child was able to open the door with his thumb latch.
   这个孩子能够用他的拇指扣打开门。
2. 2. The car key had a thumb latch that made it easy to remove.
   汽车钥匙有一个拇指扣，很容易就能取出来。
3. 3. The old man used his thumb latch to open the window.
   老爷爷用他的拇指扣打开了窗户。