第18题: [单项选择]Nancy was surprised that they have ______ . They seemed to be a happy couple. A. split up B. broken down C. fallen through D. cut off 参考答案:A 答案解析:动词短语辨析题。split up意为“分裂,离婚”;break down意为“(精神方面)垮掉;(健康)变得衰弱,崩溃”; fall through意为“失败,成为泡影”;cut off意为“隔离,中