43. I think they’re keeping it __________ (秘密).

42.They __________ (更喜欢) life On Mars.

41. Why has no one from other planets sent us _________ (信息)?

40. However, no one has ___________ (发现) any life in space yet.

39. Seven other planets also go _________ (绕着) the Sun.

38. There has been life on Earth for _________ (百万) of years.

37. I hear they’ve gone to Shanghai on ___________ (出差 ).

36. No one has been to the moon ____________ (最近).