1. Please decrease the volume. I’m doing my homework. The antonym of “decrease” is ……………. A. turn up b. turn down C. turn on D. turn off 2. _________ air is one of the many problems we have to solve. A. Pure B. Polluted C. Dust D. Pleasant 3. Find a mistake in one of the four underlined parts of the following sentence. We suggested "he " "to go"on holiday "to Italy", but he "didn’t agree". 4. I’m disappointed _________ people have spoiled this area. A that B. when C. if D. how 5. ________we were tired, we sat down beside the stream. A. Because of B. If C. As D. And 6/ If we throw trash onto the water, we will have to cope………. the shortage of fresh water. A. for B. in C. with D. on 7/ …………..water can cause many health problems when people drink it. A. Unpolluted B. Pollution C. Polluted D. Pollutant 8/ I suggest that you………….. solar energy to keep the environment clean. A. should use B. can use C. must use D. use 9/ Hanh cannot go to the movie tonight because she has to ……….. her little sister. A. look after B. look for C. go on D. turn on 10/ She is very tired; ……….., she has to finish her homework. A. therefore B. moreover C. so D. however