______ for ten years in a bank,Simon decided it was time to look for a more exciting job.空格处我选的是Working.答案是Having worked.什麼时候要加Having呢?
答：问题应该是：什么时候用having worked?因为它不是在working 前加having
本题考非谓语动词的作状语的用法.working 和having worked都是现在分词,前在是一般主动式,后者是完成主动式.它们的区别是：前者所表示的动作与主句同时发生,或几乎同时发生,后者表示其动作先于主句动作发生,相当于一个时间状语从句：after sth.had happened
本题句相当于：Because he had worked for ten years in a bank,Simon ...
是时间状语还是原因状语,靠自己去体会,用完成式,主要是因为有for ten years这个时间状语.
译：由于在一家银行工作了十年,西蒙感觉该去找一份更加让人兴奋的工作.
I still haven‘t heard from Jane even though I _______ to her three times last month.
空格处我填had written.答案是wrote.为什麼?
译：即使我上个月给她写了三封信,仍然没有收到简的来信,
析：从句的时间状语是last month,用一般过去时.过去完成时以过去某个时间为参照,表示在这之前就已经发生了的事情.本题句没有这个时间,没有这个意思.改成in the last month也是要用have written的.只有将主句改为一般过去时,才会用过去完成时：
I didn't hear from Jane though I had written to her three times.