My parents want to go ______ on vacation.
—Look! A book is on the floor. Whose is it? —It ______be Rick's. It has his name on it.
—______ hard Tony is working! —Yes. We should learn from him.
It's 9:30 pm, children! ______ is time to go to bed.
Attention please. The plane will ______ in five minutes.
There are many flowers and trees on ______sides of the Century Road.