She was _____ tired _____ she could notmove an inch

Once children reach the age of 18，they are encouraged to be and make a living on their own.

This year teenagers take an _______ in the soap opera The descendants of the sun《太阳的后裔》.

Everyone had an application form in his hand, but no one knew which office ___

The headmaster often comes to teachers’ office to __________some difficulties.