______children whose parents had died in the earthquake ____ sent to live with families in other cities.

Will you be ____ this afternoon , John?—-It depends. I’ m afraid I’ll be called in by my boss.

What are you looking for—I’m looking for the pen ______ my father gave me last week．

How often do you do exercise— ________.

Modern science has given clear evidence ________ smoking can lead to many diseases.(2011·天津，13)