2. 我姐姐是在五年前回国的。(C)

　　 这是一个强调句型，如果还原的话应该是：

　　 My sister returned from abroad 5 years ago.

　　 本句就是针对5 years ago 进行强调而得来的。

1. 我姐姐回国已有五年了。(B)

4. It will be 5 years _______ my sister returns from abroad.

　　 A. before　　　　 B. since　　　　　 C. that　　　　　　 D. when

3. It was the years 1990 _______ my sister returned from abroad.

2. It is 5 years ago _____ my sister returned from abroad.

　　 before 的这一用法与since等词用法很容易混淆，值得注意。

1. It has been 5 years _______ my sister returned from abroad.

　　 在句型“…long before ”中，long也可换成hours , day , weeks , some time 等。

　　 It will be hours before he arrives.

　　 要过好几个小时他才会到。

　　 It will be 2 weeks before we meet again.

　　 两个星期后我们还会再次见面。

　　 It will be some time before we know the full result.

　　 还要过一些时间我们才能知道全部结果。

　　 主句不仅有肯定式，也可有否定式。肯定结构意义为：过多久才，需要多久才；否定结构意义为：不久就……

　　 It was long before they finished their task.

　　 过了很长时间，他们才完成任务。

　　 It wasn’t long before the people took up their arms.

　　 不久，人民就开始拿起了武器。

　　 主句的时态可以是将来时，也可以是过去时，但从句的时态，要么是一般现在时，要么是一般过去时，根据具体情况而定。

　　 It will be 2 years before we graduate from the middle school.

　　 两年之后，我们才中学毕业。

　　 It was long before he began to do his homework.

　　 过了很长时间，他才开始做作业。

3．对老师的理解和祝愿。

信的开头已经写好，但不计入总词数。

Dear Mr Li,

I’m very excited to write to express my thanks to you. I am now a freshman of Wuhan University, which I have been dreaming about. Mr Li, I still remember the days when you taught me English. My English has been improved greatly because of your creative work. However, at one time, the pressure of examinations, too much homework and the high expectations made me depressed. I was tired of the warning that if I didn’t do my best, I wouldn’t have the chance to go to college. Thanks for your encouragement; if not, I wouldn’t have realized my dream. And now I really understand you. I wish more and more of your students could go to their ideal colleges. Are you still so busy? How I miss you!

Hoping to hear from you soon.

　　　　 Yours,

Li Hua