牛津实用英语语法:340 让步从句
它们由下列词来引导：although，though，even though，even if，no matter，however。有时也可以使用whatever。as也可以，但是只限于形容词+as+be结构。
Although/Though/Even though/Even if you dont like him you can still be polite.
尽管/即使/纵然/即使你不喜欢他，你仍可有礼貌一些。
No matter what you do，dont touch this switch.
无论怎样，都别碰这个按钮。
However rich people are，they always seem anxious to make more mon- ey.
无论人们多么富有，他们似乎总还渴望赚到更多的钱。
However carefully you drive，you will probably have an accident eventual- ly.
无论你开车多小心，最后你大概还会出车祸。
Whatever you do，dont tell him that I told you this.
无论如何，别跟他说这件事是我告诉你的。
Patient as he was，he had no intention of waiting for three hours.
哪怕他再有耐心，也不打算等上三个小时。
may+动词原形可用于假设情况：
However frightened you may be yourself，you must remain outwardly calm.
无论你有多害怕，外表上你仍要保持冷静。
may含有I accept the fact that(我接受这一事实)的意思：
But hes your brother!
He may be my brother but I dont trust him!
可他是你的兄弟!
尽管他是我的兄弟，可我不信任他!
但may这样用时，是另一主句的一部分，并不属于让步从句之列。should+动词原形结构可用于even if之后，正如用于条件句的if之后一样，用来表示should后面的动词原形所指的动作不太可能发生：
Even if he should find out he wont do anything about it.
即便他发现了，他也不会采取什么行动的。
它们由下列词来引导：although，though，even though，even if，no matter，however。有时也可以使用whatever。as也可以，但是只限于形容词+as+be结构。
Although/Though/Even though/Even if you dont like him you can still be polite.
尽管/即使/纵然/即使你不喜欢他，你仍可有礼貌一些。
No matter what you do，dont touch this switch.
无论怎样，都别碰这个按钮。
However rich people are，they always seem anxious to make more mon- ey.
无论人们多么富有，他们似乎总还渴望赚到更多的钱。
However carefully you drive，you will probably have an accident eventual- ly.
无论你开车多小心，最后你大概还会出车祸。
Whatever you do，dont tell him that I told you this.
无论如何，别跟他说这件事是我告诉你的。
Patient as he was，he had no intention of waiting for three hours.
哪怕他再有耐心，也不打算等上三个小时。
may+动词原形可用于假设情况：
However frightened you may be yourself，you must remain outwardly calm.
无论你有多害怕，外表上你仍要保持冷静。
may含有I accept the fact that(我接受这一事实)的意思：
But hes your brother!
He may be my brother but I dont trust him!
可他是你的兄弟!
尽管他是我的兄弟，可我不信任他!
但may这样用时，是另一主句的一部分，并不属于让步从句之列。should+动词原形结构可用于even if之后，正如用于条件句的if之后一样，用来表示should后面的动词原形所指的动作不太可能发生：
Even if he should find out he wont do anything about it.
即便他发现了，他也不会采取什么行动的。
