So: Part 2

[source: Swan 1995]

5. so … that

e.g. It was so hot (that) we could not work.

6. some formal uses

6.1 so … as to …

e.g. Would you be so kind as to help me with this document?

6.2 so … a …

e.g. It is so glorious a view. (similar to: It is such a glorious view.)

7. substitute

e.g. He was a bachelor and remained so until his death.

Part 3 to follow shortly.  Watch this space.