59. I’m looking forward to _________ your letter soon. (receive)

58. Tom is faster than any other __________ in his class. (run)

57. If anyone is ill here, the doctor must __________ for. (send)

56. I think walking long hours _________ hard for the children. (be)

55. We must clean our hands before ___________ meals. (have)

54. So far, no man has traveled __________ than the moon. (far)

53. Yesterday I ___________ that we would have a picnic in the park. (tell)

52. We __________ the Great Wall in two days. (visit)

51. The Greens _________ lunch now. (have)

50. My grandma told me an __________ story last night. (usual)