☆当“so +形容词/副词”位于句首时，引起部分倒装。如：
So expensive is the car that I can’t afford it.
So fast did John run that I could hardly catch him.
☆so that也可以引导结果状语从句。如：
One of his lungs is affected a little so that he has to rest.
☆含有so / such ... as to, ... enough to, too ... to等结构的句子可以转化为含结果状语从句的复合句。如：
We were so angry as to be unable to speak.
= We were so angry that we were unable to speak.
Jim made such a noise as to be told to be quiet by his sister.
= Jim made such a noise that he was told to be quiet by his sister.
Carl was strong enough to lift the huge stone.
= Carl was so strong that he could lift the huge stone.
The table was too heavy for one person to carry.
= The table was so heavy that one person couldn’t carry it.
