I soon found that the work I was doing had already been done by someone else.________,I was wasting my time.
Do you remember the name of the company ___________?
—Is Pro. Smith giving the speech today? —It __________ be him. He is abroad right now.
----Were you disappointed when you received the book bought through the Internet? ----Well, yes, _____. The back cover was a bit torn, but it didn’t really matter.
----Jack can’t concentrate on his lessons recently. ----Yes, that might _____ his low score in the last test.
Nothing but some ancient Chinese coins _______ in the sunken ship since they began the exploration.