—A medical team was sent to Japan by air five hours ago.—So they ______________ have arrived by now. The flight usually takes four hours or so.

I was really busy these days, otherwise I _______ to your birthday party last night.

Some of my classmates _________ after school every day.

Nobody knows for sure how dinosaurs died out 65,000,000 years ago. It _______ because of sudden changes of their living conditions.

— You  went to town last month, What  do you think of it?— Terrible . I _____ go there _____.