【正文】
ing ? of the students __________hard on __________ lessons. ? A. works。 their B. works。 his C. work。 their D. work。 his ? 15. They were all very tired, but __________ of them would stop to take a rest. ? A. any B. some C. none D. neither ? 16. The speaker raised his voice, but still couldn39。t make himself__________ ? A. hear B. to hear C. hearing D. heard ? 17. Allen had to call a taxi because the box was__________ to carry all the way home. ? A. much too heavy B. too much heavy ? C. heavy too much D. too heavy much ? 18. Don39。t be afraid of asking for help __________it is needed. ? A. unless B. since C. although D. when ? cook will be fired at once if he is found __________in the kitchen. ? A. smoke B. smoking C. to smoke D. smoked ? 20. You39。d better __________ late tomorrow. ? A. not to be B. not be C. to not be D. don39。t be ? 21. If he doesn39。t want to do it, does __________want to? ? .A. anybody else B. somebody else C. else somebody D. else anybody ? 22. Don39。t you think there39。s life on Mars? __________ ? A. Yes, I agree. B. Yes, of course not. ? C. Yes, I don39。t think so. D. What39。s wrong? ? 23. There is __________air __________water on the moon. ? A. either。 or B. both。 and ? C. not only。 but also D. neither。 nor ? 24. The water in the fiver smells terrible, people must __________ dirty things into it. ? A. be stopped to throw B. be stopped from throwing ? C. stop to throw D. stop from throwing ? 25. The surface of Mars is __________like the surface of Earth than__________ pla in our ? solar system. ? A. much。 the other B. much。 any other ? C. more。 the other D. more。 any other