1. One of my earrings has fallen off.
   我的耳环有一个掉下来了。
2. He gave his elbow a wrench when he fell off the ladder.
   他从梯子上摔下时扭伤了手肘。
3. This slangy word is falling off from English.
   这个俚语在英语中使用得越来越少。
4. Mary scraped her knee when she fell off her bike.
   玛丽从脚踏车上摔下来擦伤了膝盖。
5. The chalk fell off the desk and broke.
   粉笔从书桌上掉下来摔断了。

　1个名词解释