Use your head, _______ you’ll work out the problem.
When I handed the report to John,he said that George was the person ________.
It is said in Australia there is more land than the government knows ________.
I like getting up very early in summer.The morning air is so good ________.
—Is Bob still performing?—I'm afraid not.He is said ________ the stage already as he has become an official.
The flu is believed ________ by viruses that like to reproduce in the cell inside the human nose and throat.