请问哪些是目的状语从句而那些是结果状语从句？

表示目的状语的从句可以由that, so that, in order that, lest, for fear that, in case等词引导，例如：
You must speak louder so that /in order that you can be heard by all.
He wrote the name down for fear that(lest) he should forget it.
Better take more clothes in case the weather is cold.

结果状语从句常由so… that 或 such…that引导，掌握这两个句型，首先要了解so 和 such与其后的词的搭配规律。

比较：so和 such
其规律由so与such的不同词性决定。such 是形容词，修饰名词或名词词组，so 是副词，只能修饰形容词或副词。 so 还可与表示数量的形容词many, few, much, little连用，形成固定搭配。

so foolish such a fool
so nice a flower such a nice flower
so many / few flowers such nice flowers
so much / little money. such rapid progress
so many people such a lot of people
（ so many 已成固定搭配，a lot of 虽相当于 many，但 a lot of 为名词性的，只能用such搭配。）

so…that与such…that之间的转换既为 so与such之间的转换。
The boy is so young that he can't go to school.
He is such a young boy that he can't go to school