中學英語句子好寫，但怎樣寫好表達原因結構的英語句子還需要很多技巧。石家莊中學英語老師為學員提供實例進行講解：
考生病句：
1、The real reason to our failure is not far to seek.
2、The reason for this is because some people want to earn plenty of money without
working hard.
正確表達：
1、The real reason for our failure is not far to seek.
2、The reason for this is that some people want to earn plenty of money without working
hard.
評議與分析：
以上兩個病句分別引自92年1月和97年12月四級考試考生作文。從遣詞造句上看，這兩位考生具有一定寫作能力，not far to seek, plenty of money以及without working hard等均運用正確、恰當。但令人遺憾是，*位考生不知道reason不與to搭配而應接介詞for，第二位考生犯了一個*學生常犯錯誤，就是用because引起表語從句，because這個詞不能引起表語從句，在本句中只能改用that才正確。掌握好表達原因結構是十分重要，幾乎所有寫作試題都要求寫原因或可以寫原因。寫作文體基本上是議論文，而議論文基本模式是擺事實、講道理，講道理就是說明原因。寫作測試文體決定了表達原因結構重要性。
中學英語中用來表達原因這一概念結構有多種。我們可用as , because, since, seeing that, considering that, now that, not that...等詞組引出表示原因從句。例如：
1、Since we live near the sea, we enjoy a healthy climate.
2、Professor Liu is strict with us because he wants us to make rapid progress.
3、Now that we have seen these great achievements with our own eyes, we feel more
proud than ever of our country.
4、Pollution is still a serious problem, not that we don't have the ability to solve it, but that
some people have not realized the consequences of the problem.
我們可以借助某些詞語用簡單句表達原因結構。例如：
1、Idleness is the root of all evils.
2、Diligence is the key factor of success.
3、The reason for this change is quite obvious.
4、He was ashamed to have made the mistake.(=He was ashamed that he had made the
mistake. =He was ashamed because he had made the mistake.)
除了上述例句外，英語中還有很多或易或難表達原因結構。我們在進行英語寫作訓練時候，不能滿足于一知半解，要講究書面語言正確性和準確性。比如，because是最常用引導原因從句連詞，語氣最強，表示直接原因，若because置于句首，后面主句不能再用so。用as引導原因從句語氣較弱，所說明原因是附帶，而since表示原因暗示著是稍加分析之后才能推斷出來原因。
