The island where these rare birds nest has been declared a _____.
--Has the train arrived yet?---No, it ought to ___ twenty minutes ago.
I didn't expect that so many people ___ to join in the work.
Mr.Brown ___ goes to bed before midnight.
Mr. Green always goes to ___ cinema on Sunday afternoon, while his wife goes to ___ church on Sunday morning.
Young people who have got jobs may realize university lessons can’t be the only preparation for all of the situations____appear in the working world.