1. nobody后用第三人称单数

2. 虚拟语气

条件句可分为两类，一类为真实条件句，一类为虚拟语气。

1. 真实

   • If he doesn't hurry up, he will miss the bus.如果他不快点，他将错过巴士。( 真实)

2. 虚拟

   • If I were you, I would go at once.
     如果我是你，我马上就会去。（我不可能是你。非真实，所以虚拟语气）
   • If I knew his telephone number, I would tell you.
     如果我知道他的电话号码，我就会告诉你。（事实：不知道）
   • She looks at me as if I were a stranger.
     她看我的样子，好像我是个陌生人（事实：不是陌生人）
   • If he were free today, we would have sent him to Beijing.
     如果他今天有空的话，我们就已经派他去北京了。
   • If he knew her, he would have greeted her.
     要是他认识她的话，他肯定会去问候她了。
   • He would have finished it. 他本该完成了。
   • You could have passed this exam. 你本能通过这次考试的。

3. 表示与过去事实相反的情况

   • If I had got there earlier, I would have met her.
     如果我早到那儿，我就会见到她。（事实：去晚了）
   • If he had taken my advice, he would not have made such a mistake.
     如果他听了我的劝告，就不会犯这样的错误了。（事实：没有听我的劝告）
   • If I had worked hard at school, I would be an engineer too.
     如果我在学校学习刻苦的话，我现在也会成为一个工程师了
   • If they had informed us, we would not come here now.
     如果他们通知过我们的话，我们现在就不会来这里了。

4. 表示猜测

   • Tom could have taken the money, he was here alone last night.
     Tom昨晚一个人在这，他可能拿走了钱

3. remember to do/remember doing

• remember to do 意思是记住去做某事,表示这件事情还没有做
• remember doing 意思是记得做过某事,表示这件事情已经做了

4. be doing表将来！

we are having a test next week.
我们下周有场考试

5. been/being

1. been为be的过去分词,常和have连用表示完成时态
   • I have been in Beijing for three years.
     我已经在北京呆了三年了.
2. being为be的现在分词形式.
   1. being可以当作被动语态
   • I'm always being criticized.我总是挨批.
   • He is being interviewed now.他现在正在接受面试.
   • Being lost can be a terrifying experience.迷路可能是一种很可怕的经历.
   • Being recognized wherever you go is the price you pay for being famous.出名所付出的代价是不管你走到哪里,都会被人认出来.
   • I saw him being taken away by the police. 我看到他正被警察带走.