英语中有些句子形式上是否定的，但是内容含义上却是肯定的。现将这种常见的句式结构归纳如下：

一、 cannot wait 后跟不定式， 意为“急于做”，表示强调的肯定

例1 I couldn‘t wait to see her. 我渴望见到她。

例2 I cannot wait to read the book. 我非常渴望读到这本书。

二、 cannot/couldn‘t+too意为“越……越……　，非常，无论怎样……也不过分”

在此结构中，cannot 也可改用can hardly，scarcely，never，impossible;too也可改用over，enough等。

例3 You cannot be too careful. 你越小心越好。

例4 We can hardly praise him too much.对他我们无论怎么赞扬也不过分。

例5 A man can never have too many friends. 朋友越多越好。

例6 He cannot see you quickly enough. 他想很快见到你。

三、 not… until/ till 意为“直到……的时候才”

例7 People take no thought of the value of time until they lose it. 人们失去时间后才知道时间的价值。

例8 We never know the worth of water till the well is dry. 直到井干了我们才知道水的重要。

例9 It was not until the next day that I knew that truth. 直到第二天我才知道真相。

例10 He did not go to bed until his mother came back. 直到他母亲回来他才睡觉。

四、否定词+but

1. no…but 意为 “都……， 没有……不……”。

例11 There is no man but has his faults. 人皆有过。

例12 No one believes but she will succeed. 人们相信他会成功。

例13 There is no one but knows him. 人人都认识他。

2. never (not)…but (that) 意为 “每当……， 总是……， 没有哪次不是……”。

例14 I never see you but I think of my mother. 每当看见你时，我总是想起我的母亲。

例15 It never rains but it pours.每次下雨都是倾盆大雨。

例16 He will not be angry but that he is offended. 人们惹了他他才会生气。

3. nothing but /none but 意为 “仅仅，只，只有……才”。

例17 We can see nothing but water. 我们只能看见水。

例18 The boys want to do nothing but play football. 男孩们只想踢足球。

例19 None but me knew what happened. 只有我知道发生了什么事情。

例20 He chose none but the best. 他只选最好的。

五、 not long before 意为“不久……就……”

例21 It was not long before he appeared. 他不久就出现了。

例22 It will not be long before we finish the experiment. 我们不久就完成了实验。

六、 否定词+without 意为 “ 每……必”

例23 I never see her without thinking of my younger sister. 每次见到她，我就想起我的妹妹。

例24 What appeared to me wonderful was that none of the ants came home without bringing something. 使我感到惊奇的是每只蚂蚁回来都带回一些东西。

例25 There is no smoke without fire. 有烟必有火。

七、 no(none) other than意为 “仅仅，完全”

例26 This is no other than the book we want to buy. 这正是我们要买的那本书。

例27 She is none other than my teacher. 她正是我的老师。

例28 The letter was written by none other than Mary. 写这封信的正是玛莉。

八、 too + 形容词 / 副词 + not + 不定式 “非常……必定能， 太……不会不”

1. 本句型是对too … to 的否定，表示肯定意思。

例29 His speech was too good not to stir the audience. 他的演讲太好了，不会不使观众轰动。

例30 He is too wise not to solve this problem. 他那么聪明，一定会解决问题。

例31 He is too foolish not to say it. 他那么傻，不会不把这事说出来。

2. 若 把否定词放到前面not too … to 表示这并不太……所以能。

例32 English is not too difficult to learn. 英语没有难到不能学的程度。

例33 He is not too old to do it. 他做这件事，年龄并不老。

3. never too … to (永不/决不……)。

例34 It is never too late to give up prejudices. 放弃偏见永远不晚。

九、 more often than not意为 “常常，往往”

例35 John is a good swimmer. He wins more often not. 约翰是个游泳健将，他常常在比赛中获奖。

例36 During bad weather the trains are late more often than not. 在天气不好时，火车常常晚点。

例37 The street is crowded more often than not.这条大街常常很拥挤。

十、 否定词+比较级( 相当于最高级)

例38 I couldn‘t agree more. 我非常同意。

例39 Nothing is more valuable than health. 健康是最宝贵的。

例40 Never is more beautiful flower than this!这是我见过的最美丽的花!