大学英语：escape v.逃跑，避免

　　A lion has escaped from its cage.

　　一头狮子从笼子里跑出来了

　　2 exert： vt.用尽;尽力;运用;行使;施加，产生(影响等)

　　用法：exert pressure on sb.给…施加压力

　　She exerted herself all year to earn good marks.她整年努力以期获得好分数。

　　He's been exerting a lot of pressure on me to change my mind.他一直在施加种种压力要我改变主意。

　　Black holes exert very strong gravity.黑洞产生很强的引力。

　　3 explode v.爆炸，突发

　　xplosion n.

　　explosive a.

　　A bomb exploded at one of London's busiest railway station this morning.

　　今天上午一颗炸弹在伦敦最繁忙的火车站爆炸了。

　　4 collapse v.n.倒塌， 崩溃

　　例句 参考教材第34-35页的 word Study 2