71. Only by _______________（科学的）training can Liu Xiang make such rapid progress in the 110-meter hurdle.
72. His words left me the ___________________ （印象）that he didn’t like the plan at all.
73. The United Kingdom __________________（组成）of Great Britain and Northern Ireland.
74. He had never been knocked out in a __________________（职业的）fight.
75. It is said that you will be affected by the ________________ （辐射）if you talk on the mobile phone for long.
76. The ________________（火山爆发）of a volcano often brings lava and ash clouds.
77. We will have an opportunity to ________________ （交换）views tomorrow.
78. People can easily become __________________（精神上）addicted to drugs when they start taking them.
79. It is OK to leave an _____________（电的）appliance on as long as you are using it.
80. Having guaranteed that we would get there before five ,I _____________（惊慌）.