Why does your brother _______ a sad look on his face these days?
You _________think you're clever, but that doesn't give you the right to order me about!
--Jack's won _____________ holiday in London.--_________ lucky fellow !
____________ great help, I could get rid of all the difficulty and succeeded.
The reason__________ their failure you know is they didn't get fully prepared for the experiment.
--Why has he been staying at home these days?--He ___________ since a month ago.