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reason 的用法应注意以下几点：
1)表示理由或原因，多用作可数名词，有时也用作不可数名词，其后常接介词for-短语或不定式短语：
Give me your reason (s) fordoing it. 说说你做这件事的理由吧。
I have many reasons tofear him. 我怕他是有很多理由的。
There is (some) reason tosuspect him. 怀疑他是有 (些)理由的。
The reason for the floodwas all that heavy rain. 涨洪水的原因完全是那场大雨。
2)后接定语从句，用why (=for which)引导，有时也可用that, 在非正式英语中甚至可以省略：
The reason that [why] he died waslack of medical care. 他死的原因是缺少医疗。
The reason I didn’t tell you was that I wanted it to be a surprise. 我之所以没有告诉你是想让它给你个惊奇。
注意the reason之后所接的why引导的定语从句，必须是限制性的，而不能是非限制性的。
3)在 The reason why…is that…这类句型中，通常要用 that来引导表语从句，但在现代英语中用 because的情况已比较普遍：
Thereason (why) he did not come was that [because] he was ill. 他没有来是因为他生病了。
但在应试中，若要从that / because中作出选择，当然以选that为宜。
2. The government has been pressing the companies to give up concessions that give them a share of profits from oil fields and to accept service contracts instead.
that give them a share of profits是定语从句，修饰concessions。to give up和to accept是两个并列的成分，都是pressing的内容。
