根据下列句子及所给单词的首字母,答题纸上按题号写出各单词的完全形式(每空限填一词)。

71. .My parents both work late u         midnight. It is bad for health.

72. My father t_______ in this school and his students love him very much.

73. I don’t think he is an h         boy. He always tells lies.

74. Christmas Day is in the t         month of the year.

75. I think the light bulb is one of the most helpful i_________.

76. My mother always asks me to go s         with her，but I don’t like buying clothes.

77. Take this m________ three times a day ,and you ‘ll be OK in three days .

78. Though she was only seven ,she could look after h______ her parents were busy .

79. I think if I work hard on my lesson ,my d____     will come true one day

80．What were you doing b           2:00 and 4:00 yesterday afternoon?