Marcus is our foreign teacher．He _______ in our school for two years．（ ）
A．wasB．will beC．has been
Most of us enjoy __________to our mothers speak， because our brains greatly prefer the voices of our own mothers．（ ）
A．listeningB．listenC．to listen
Kelly White loves all sports， __________skating．（ ）
A．graduallyB．seriouslyC．especially
Only plants and animals that need very little water __________live in a desert．（ ）
A．canB．needC．must
It's hard to turn down a banana． They taste good and you don't have to wash them __________eating them．（ ）
A．untilB．afterC．before
Thanks for letting us borrow your camera． We __________it to you next Monday．（ ）
A．returnB．will return
C．have returned