I my homework at home this morning.
Our headmaster isn’t in his office. I can’t find him anywhere. Did you notice him ______ the office?
You had better ________ some time every day for sports so that you can keep yourself energetic.
The radio says that a terrible traffic accident happened sometime ________ 8 a.m. ________ 10 a.m. this morning.
He made a mistake, but then he took action to change the situation ________ it got worse.
Having ________ exercise every day will do great good to your health.