用本单元中的生词补全句子

He e________ the blue jumper for a red one.

根据句意用本单元中的生词填空

Mary said she learnt Chinese by l ________ to cassettes.

根据句意用本单元中的生词填空

You must s________ your ticket to the conductor when you get on a train.

根据句意用本单元中的生词填空

There is p________ more paper if you want.

根据句意用本单元中的生词填空

I think this is a f________ good book.