I should have written the letter earlier. But I have been very busy.
　　要能登上珠穆朗玛峰，那经历该多棒!
　　It would be a fantastic experience to climb up to Mount Everest.
　　6、虚拟语气省略条件从句或主句
　　表示虚拟语气的条件句的主句或从句有时可以省略，而省略部分的含义仍有所体现。
　　1)省略条件从句，如：
　　It would be very nice.
　　You could have done it yourself. (省略If you had wanted to.上下文可以看出You didn’t want to.) (Fact: You didn’t do the work yourself because you didn’t want to.)
　　I wouldn’t smoke. (省略If I were you.) (表面上说我，实际上说你。这是一种委婉的表达法。(Fact: You smoke very often. I advise you not to smoke any more.)
　　2)省略主句：在强调条件从句时，常省略主句，这种句子常表示一种“已不能实现”的愿望，主要用于If only 引导的感叹句中。
　　For example:
　　If only he were here!
　　If only I knew more!
　　If only he had stayed with us!
　　Now let’s do some translation:
　　要是我听了他的建议就好了!
　　If only I had taken his advice!
　　我如果是一只鸟就好了!
　　If only I were a bird.
　　快用If only 造三个句子，表达你的愿望!
　　If only I could live in a big apartment!
　　If only I were a billionaire!
　　If only I could marry her/him!
　　(二)虚拟语气的其他句型和用法
　　1、用在“wish+宾语从句”中，表示很难实现或不能实现的愿望，可以翻译为“但愿…”, “悔不该…”等。表示现在不能实现的愿望，从句的谓语动词用过去式;表示将来的愿望，从句的谓语动词用“would (could)+动词原形”;对过去的事情表示愿望，从句的谓语动词用 “had+过去分词” 或“could + have + 过去分词”。Wish 后面的宾语从句必须用虚拟语气，不管这个愿望是否能实现。如：
　　I wish it were Spring all the year round.
　　I wish you could go with us.
　　We wish we had arrived there two hours earlier.
　　Now let’s do some translation using “wish”:
　　我要是Jane 就好了。
　　I wish I were Jane.
　　他真希望自己生活在中世纪。
　　He really wishes that he were living in the Middle Ages.
　　但愿北京整年是秋天。