—The research on the new bird flu virus vaccine is challenging and demanding. Who do you think can do the job?—____ my students have a try?

—I visited China year. —That          interesting.

—— I can’t get through to the general manager’s office anyhow. —— The line is busy. Someone＿＿＿＿＿the telephone. 

If I _________ ten years younger, I _________very happy.

“Is John coming by train?” “He should, but he _________ not. He likes driving his car.”