1. We can say a lot of things about those who are devoted to poems in their whole lives (一生致力于诗篇的人). They are passionate, impulsive and unique.
2. Mary couldn’t have received my letter, or she should have made a reply last week. (不然她上星期就该回信了).
3. Nancy is supposed to have finished her chemistry experiment(做完化学试验) at least two weeks ago.
4. Never once has the old couple quarreled with each other (老两口彼此争持)since they were married 40 years ago.
5. The prosperity of a nation depends largely on (一个国家未来的昌盛在很大程度上有赖于) the quality of education.