given back的用法和样例：
例句
- I must give back the two books to the library before Friday.
星期五之前我必须把这两本书归还图书馆。 - A letter for me left, by mistake, at my neighbor's house was kept for two days and then given back to the postman.
我的一封信误投给邻居了，在那里放了两天之后又退给了邮递员。 - Has he given back the tools he borrowed from you?
他向你借的那些工具归还了没有？
