一、 at, in
例1 Both Mary and Betty will get married this year. Mary is going to begin their honeymoon
Christmas while Betty _____New Year’s Day.
A. on; on B. at; in C. at; on D. by; on
评析 此题选C。at主要用来表示时点，但也可以表示时段，主要用在某些一年中重要的节日名称之前，不仅表示节日的当天，而且也表示整个节日的期间。但如果节日名称后面紧跟day，那就是表示节日当天，不能用at，而要用on。
例2 Suffering from the terrible earthquake, the victims often awake several times _____the night and sometimes they even cannot sleep _____night.
A. in; at B. at; in C. during; in D. in; during
评析 此题选A。at night表示整个夜晚，或指白天结束、夜幕刚降临时，而in/during the night则指夜间的某一时刻。
