---Is Jack on duty today? ---It ________ be him. It's his turn tomorrow.
11. How time flies! You should make _____ use of your time.
10. East and west, home is _____.(prov.)
9. Some girls are _____; a few, but very few, are _____.
8. --- How is your friend now? --- I am sorry to tell you he is going from ____ to worse in the hospital.
7. David was lying in bed, _____ , listening to an English pop song.