--- Would you mind giving your advice on how to improve our efficiency?--- If you make      most of forty-five minutes classes day after day, there will be       switch in grades.

—What do you think of the manager of your company?　　　　—Oh, he is ________ manager who’s pleasant to work with.　　It’s ________ pleasure to work with him.

They stole the goods in the store and were put ____.

--How do you pay the waitress?  ---As a rule, they are paid ____.

While other scientists are keeping____eye on changes in the H5N1 bird flu strain, the scientists in England are working on vaccines, in case it becomes highly infectious in ____humans.