例句：

　　Get everything in writing in order to cover your back.

　　一切都要立字為據(jù)，以絕后患。

　　Water covers a large proportion of the earth's surface.

　　水覆蓋了地球表面的大部分。

　　The book aims to cover all aspects of city life.

　　這本書旨在涵蓋城市生活的各個(gè)方面。