USE
"So" can be combined with adverbs to show extreme actions. This form is often used in exclamations.
Examples:
* She spoke so quickly! She sounded like an auctioneer.
* He paints so well! I am sure he is going to become a famous artist.
USE with "That"
The above form can be combined with "that" to show extreme actions which lead to certain results. The "that" is usually optional.
Examples:
* She spoke so quickly that I couldn't understand her.
* She spoke so quickly I couldn't understand her.
* He paints so well that they offered him a scholarship at an art school in Paris.
* He paints so well they offered him a scholarship at an art school in Paris.
