1.Your mother asked me to tell you that

(你不必为她的健康担心).

2.

(他花了三个多种头)to translate the article from English into Chinese.

3.It is well known that

　　　　　　　　　　　　　　　　　　　　 (地球表面百分之七十以上为水覆盖).

4.Ways must be found to

(防止这个工厂把废水排到河里).

5.If the wounded driver had been treated without delay,

(他就可能得救了).

6.What I see in the city today

(和我三十年前住在这里时所见到的完全不同了).

7.My opinion is that

(你刚才问的那个问题和我们的计划无关).