Tom ________ in the library every night over the last three months.(2011·北京)
A．works B．worked
C．has been working D．had been working
In order to find the missing child，villagers ________ all they can over the past five hours.(2012·安徽)
A．did B．do
C．had done D．have been doing
—Hi, Susan, where were you at lunch time？I ________ a seat for you in the coffee shop.
—Oh, sorry to miss you.My political science class ran longer than usual.
A．am saving B．was saving
C．had saved D．have saved
—Mum, you should have taken me to the park this morning.
—I had planned to, but I couldn't afford the time.I ________ a lecture.
A．had given B．gave
C．was giving D．would give
—When did the computer crash?
—This morning，while I ________ the reading materials downloaded from some websites.(2012·福建)
A．have sorted B．was sorting
C．am sorting D．had sorted
After school we went to the readingroom to do some reading，only to be told that it ________.(2012·安徽)
A．was decorated B．had decorated
C．had been decorating D．was being decorated
