小题1:We enjoyed ourselves this New Year’s Day this year.
小题2:My uncle sent me a card yesterday to congratulate / congratulating me on my 18th birthday.
小题3:After years of / years’ construction, the little town is now as lively as it was before the earthquake / it
used to be before the earthquake.
小题4:The performance began with a piece of classical music which was familiar to people in their fifties.
小题5:No sooner had she watched the TV program on the extinct species than she made up her mind to join the wildlife protection organization.
小题1:根据“今年元旦”可知，该句用一般过去时，玩得很开心用词组enjoy oneself
小题2:根据“昨天”可知，该句用一般过去时，congratulate 的用法是congratulate sth或者congratulate sb on sth
小题3:根据“经过多年的建设”可知，后面描述的是建设后的情形，即现在的情形，因此用一般现在时，as..as..的用法是形容词或者副词放在中间。
小题4:根据句意可知，演出已经开始了，事情发生在过去，因此用一般过去时，familiar的用法是sb be familiar with sth 或者sth be familiar to sb
小题5:no sooner的句型为no sooner ...than,因为no sooner是否定词，因此no sooner后面要用部分倒装的句式。