31. If you don't study hard, you won't be able to pass the exam.

32. If they don't have enough money, they can't buy a new car.

33. Unless he can't find a companion, he won't be traveling this summer.

34. Although she tried very hard, but did not succeed.

35. I haven't played tennis since the last time in 1908.

36. We were having dinner when the phone rang.

37. We spent two two hours repairing windows yesterday.

38. My mother likes to watch news on VTV1.

39. If I could, would you allow me to get these bottles from the bottle bank?

40. The kangaroo is the symbol of Australia.

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