89.Mary goes to keeping-fit classes and does exercises every morning.
玛丽每天早上去健身班做操.
90.The idea that computers can recognize human voices surprises many people.
计算机可以识别人的声音,这种想法使很多人感到惊讶.
91.They watched the game, and were invited to join in.
他们先观看比赛,后来被邀请参加.
92.He set an example to his colleagues by his hard working spirit.
他以自己努力工作的精神为同事们树立了榜样.