Since the introduction of the new technique, the production cost____ greatly.

A. reduces
B. reduced
C. is reducing
D. has been reduced

By the time you get there tomorrow, they___ for Beijing.

A. will have left
B. are leaving
C. will leave e
D. are to leave

A young man stood nearby while I (read) ______the newspaper.

There (be) _____ several such occurrences in the past few weeks.

Look, the cat (run) ____ after the mouse.

John (go) ____ to the doctor’s today because he felt ill.

No sooner had they gone to the plant than they (start) _____ to work.

They fulfilled the task assigned by their teacher earlier than they (expect) ____.

He (take) ____ off his hat and bowed politely as he passed.

写一篇英语作文,要求用到的时态不少于四种