----You look tired, Jack. ----I feel quite rested, _______.

 He saw the MP4 player a moment ago, but he didn’t know how it disappeared _______.

The dog, if trained _____, will be made a good watch-dog one day.

—In early autumn Steve applied for admission to college. He wanted to go      but to Cornell University.—Oh, why not Harvard?

 When you feel you are happier and more relaxed after having a cigarette, you may become ________addicted.