English的改错题

1.The United States is composed of fifty states,two of those are separated from the others by land or water.

错误是two of those如何改？

2。Nancy had a great deal of trouble to concentrate on her work because of the noise in the next room.

错误是to concentrate on 这怎么错了？

3.Even though she looks very young,she is twice older than my twenty-year-old sister.错误是twice older than 这两倍怎么改？

4.Those of us who work in chemical laboratories should have their lungs checked quite regularly.

错误是their 为什么/

1. two of those 改成 two of which

2. to concentrate on 改成concentrating on。原因：have trouble （in）doing sth是固定句型。

3. twice 改成 two times

4. their 改成 our 。 原因：第三个单词us

two of whose

concentrating on

twice as old as

没错啊