常用情态动词的基本用法ought和need
ought 应该（后接带to的不定式构成谓语动词）
（1）表示出于职责、义务该做某事
You ought not to be so careless in your work . 你不应该在工作上如此粗心大意。
We ought to study hard for the sake of our motherland. 我们应该为了我们的祖国而努力学习。
His doctor said to him that he oughtn't to smoke so much . 他的大夫说他不应该抽这么多烟。
Oughtn't you to give us a chance to try ？ 你难道不应该给我们一个尝试的机会吗？
（2）表示极有可能发生某事
As an auto repairman , Dick ought to know what is wrong with the car .
狄克作为一个汽车修理工总该知道这部车的毛病所在吧。
If we set off right now , we ought to be able to get there in time .
如果我们马上出发，我们应当能够按时到达那里。
Tomorrow ought to be a nice day for we have such a fine sunset today .
今天有这么好的晚霞，明天准是个晴天。
不知不觉背单词
随时随地背单词
新概念英语青少版
need需要（用于否定句和疑问句）
There are still one and a half hours to go , we needn't be insuch a hurry .
还有一个半小时，我们无需如此慌慌张张。
I hardly need say how much we missed you . 不用说我们是多么想念你啊。
Need you go so soon ？ 你需要这么早就去吗？
You need have no anxiety on my account . 你不必为我而着急。
1. It was really annoying; I _____ get access to the data bank you had recommended.
A. wouldn’t B. couldn’t C. shouldn’t D. needn’t
2. Had the governments and scientists not worked together , AIDS-related deaths _______ since their highest in 2005.
A. had not fallen B. would not fall C. did not fall D. would not have fallen
3. —Can’t you stay a little longer?
—It’s getting late. I really _____go now, My daughter is home alone.
A .may B .can C . must D .dare
4. Without his wartime experiences, Hemingway____ his famous novel A Farewell to Arms.
A. didn’t write B. hadn’t written
C. wouldn’t write D. wouldn’t have written
5. You ____ be Carol. You haven’t changed a bit after all these years.
A. must B. can C. will D. shall
1. B 【解析】试题分析：句意：这真是令人生气的；我不能进入你推荐的数据库。wouldn’t不愿意；couldn’t不能；shouldn’t不应该；needn’t不必。故选B。
2. D 【解析】试题分析：句意：如果政府和科学家不共同努力，艾滋病相关的死亡就不会从2005年的最高点下降。使用虚拟语气， if条件句用的had done，而且省略it，将had提前，主句用would have done表示对过去情况的虚拟。故选D。
3. C 【解析】试题分析：句意：——你不能再多待会儿吗?——很晚了，我必须得走了。我女儿一个人在家。A. may可能，可以，也许；B. can能，会；C. must必须，必然要，必定会；D. dare敢，胆敢。结合句意，故选C。
4. D 【解析】试题分析：句意：没有他战时的经验，海明威就不可能写出著名的小说永别了武器。根据without his wartime experience没有战时的经历，可知表示对于过去的否定猜测，故主句用would have done，因此选D项。
5. A 【解析】试题分析：句意：你肯定是卡罗，这些年你一点也没有变化。 must表示对现在的肯定推测。故选A。
