--- Listen ! Who _______in the room? ---Let’s go and see.
---It was ___________ who helped us out of danger. ---What brave and helpful children! We should learn from them.
My mother was doing the cleaning in the sitting room ________ the telephone rang.
Every day, too much water _______ in our school. We should save it.
— Must we go to see a doctor at once when we have the flu? —No,_____. A. we mustn’t B. we shouldn’t C. we don’t have to
— ____ you _______your book to the library? — Yes. I returned it yesterday. A. Did, return B. Have, returned C. Will, return