It was the second time that I_______of the changes of the timetable .

My classmate Andrew went to Vancouver , Canada in 2005 , and_____since .

The world economic crisis _______ in 2008, but the global economy began to recover in the second half of 2009.

I didn’t know  this years ago ,but recent science ____that inharmonic marital(婚姻的) life like quarrels or fights harms one’ heart.

Gary Locke , a Chinese-American , once______ as the governor of Washington for 8 years and now is U. S. Commerce Secretary.

The number of foreign students attending Chinese universities____rising steadily since 1997.

“I________in the room, watching TV broadcast about the earthquake.” I told the policeman who had driven here to question me.

The computer looks old, but it _________ just half a year ago.

--- How come your father can read books in German?
--- Well, he____on a project with some German engineers for 3 years when he was young.

--- Have you heard that Jones, along with her parents,____to Hainan for the winter vacation?
--- Really? No wonder I haven’t seen her these days.