.--- He has to finish the experiment today. He must be in the lab,____?---That s quite possible.
I called the airline to _____ my flight reservation a week ago.
My friend, Tom, left New York in 1976 and _____ since then.
China _____ a sharp increase in the number of Social Networking Services users in the past years.
The two giant pandas are so much alike that it is impossible to ________ one from the other.
—Did you look up the time of the trains to Shanghai? —Yes, the early train is ________ to leave at 5:30 am.