The research on the new flu virus vaccine ischallenging and demanding. Who do you think can do the job—____ my students have a try

Kitty was a little fat last year, but she is ______ now.

Why is your English so good, Amy? — Well, my uncle gives me a hand at home, for he _____in Australia for ten years.

_________ advertisements are of great help, I don’t think we should entirely rely on them

twelve o’clock, I think I must be offnow” “Oh, reallyI ______ it at all”