21. The factory p                 over 550 cars last month.

22. --- Which language is spoken most w                 in the world?

--- English.

23. Lingling studied in the l                 school in her village two years ago.

24. Li Yundi won the first prize in the 14th i                 piano competition.

25. The teacher try their best to make their lessons l                 and interesting.

26. There are many kinds of plastic p                 in the department store.

27. --- Can you c                 your homework before dinner?

--- Yes, I can finish it in ten minutes.

28. When the t                 lights are red, the cars must stop.

29. Everyone should a                 talking loudly in the library.

30. When we learn English, we should pay more attention to the e                 English.

31. This kind of TV set is p                 in China.

32. Is English w                 used in your country? As I know, more and more people are learning it at school.

33. My father is a teacher at our l                 school.

34. English is the language of i                 travel.

35. There was a l                 discussion in our class. Everybody gave his or her ideas.

36. While comparing prices, we should also consider the quality of the p                .

37. She had trouble making c                 sentences.

38. Tianjin plans to start a smart city program to deal with t                 jams.

39. The lazy man tried his best to a                 doing his work.

40. Our English teacher tells us to speak e                 English every day.

41. Maybe one day, teleportation could become a reality and people could                 (避免) traff