——I haven't got a camera.——I think you should buy_______. It's useful for you.
I was doing my homework________my father was reading newspapers. A.how B.while C.if
—I was at the cinema at 9 o’clock last night.What about you? —I________at home.
—Do you know________? —This afternoon.
We were________surprised that nobody believed that it was true.
The bridge________by the villagers last year.