’t believe that Jeff _______ havequarreled and fought with his boss– Well, if one _______ ask for trouble, it just can’tbe helped

Some people plan to ______ a volunteer program to help the disabled children.

In some cities the traffic police use computers to keep the traffic________smoothly.

He likes novels very much , while I love science fiction _________

We’re doing a lot to protect ourenvironment, but it is not good enough. —Sowe should try______ to look after it.