34. -Are you sure you have to? It’s been very late.-I don’t know ________ I can do it if not now.
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.
________ ,loss implies gain; on the other hand, gain implies loss.