key drop

• 钥匙孔盖片

key drop的用法和样例：

例句

1. As he picked up the envelope, a key dropped out.
   他拣起信封时，一把钥匙掉了出来。
2. As she picked up the envelope, a key dropped out.
   她拾起信封时，一把钥匙掉了出来。