单词拼写（共10小题；每小题1分，满分10分）
根据题中所给的首字母写出符合句意的单词的正确形式。
71. This kind of drug can p_________ children from mosquitoes.
72. The noise outside a__________ our study.
73. Tom works so hard, so he will s_________ sooner or later.
74. There are many kinds of i_________ in the world, a bee is one kind of them.
75. Sea water c__________ salt.
76. You will e__________ your health if you work so hard.
77. She prefers pop music and jazz to c__________ music.
78. A m__________ is a person who performs or writes music, especially as his/her job.
79. Police asked some p__________ to get some evidence about the accident happened just now.
80. The group of popular singers will give another two p__________ before leaving China.