句用一般现在时态，表示一般将来时。
If you make a lot of noise,you may disturb others. 如果你弄出噪音，你就会打扰。
If it doesn’t rain tomorrow,we will go to the park. 如果明天天不下雨，我们就去公园。
注：以when,before,until等引导的时间状语从句，也有此用法。 When the traffic light is green,you can cross the road. 当交通灯是绿色时，我们可以过马路。 Don’t say that before you read the story. 在你没读故事之前，不要那么说。
People in the US can’t drink beer or wine before they reach 21. 在美国人们在21岁之前不能喝酒。
26.The car nearly hit you.车几乎撞到你了。［L.65］ nearly与almost区别
nearly副词，意思是“几乎，将近”，与almost同义，但almost在程度上较更为接近，当所选程度很难衡量时，只用almost不用nearly。nearly不能修饰all,every,never,nothing,nobody等表示全部肯定或全部否定的词，但almost可以。
Almost all the students went to the farm. 几乎所有的学生都去农场了。
27.It is better to wait and be safe.［L.65］ 最好等到安全的时候。 类似句型：
It is best/better to do =You had better do sth. 最好做某事
It is better to wear warm clothes.=It is best to wear warm clothes.=You’d better wear warm clothes.
你最好穿暖和的衣服。
28.Do you think it necessary for us to learn to wait?［L.66］ 你认为对于我们来说学会等很必要吗？ 句型：主语+think/feel/find it+形容词+(sb.)+to do sth.表示某人认为/发现/感觉干某事对某人来说
Do you think it important for us to learn English well? 你认为对于我们来说学好英语很重要吗？ I find it hard for us to do this work.
我发现对于我们来说，干这个工作很难。
29.At the head of the queue was an old woman.［L.66］ 在队伍最前面是位老妇人。
倒装句，正常语序为：An old woman was at the head of the queue. Here comes the bus.公共汽车来了。
Lucy likes English,so do I.露西喜欢英语，我也喜欢。 30.She sat nearest to the doctor’s door.［L.66］ 她坐在靠诊室最近的地方。
nearest to是短语near to(靠近，接近)的最高级，nearer to是比较级。近义词是next to。 He asked us to sit nearer to him. 他让我们坐得离他近一点。
