第二节完成句子（共5小题，每空1分，满分10分）
71. The police came and____________ ____________ the crowd.（驱散）
72. ____________ ____________, Mike has learnt how to use chopsticks.（另外）
73. After we heard the news that the kid had been found, we sighed ____________ ____________.（松了一口气）
74. This is the home I have always ___________ ____________. （梦想）
75. We should never waste anything. _____ ______, we should not waste time.（最重要，首先）
