[susan53]

I deleted the first answer because it clearly confused you. Trying again...

So is an intensifier which is used before adjectives, adverbs and quantifiers. For example :

- so + adjective : I've never been so surprised!
- so + adverb : The time went so quickly!
- so + quantifier : I enjoyed it so much!

Such is used with noun phrases - which may contain a pre-modifying adjective, but this is grammatically incidental. It's not the head of the phrase and could be omitted: I've never seen such (bad) behaviour!

Such cannot be used with quantifiers. Even when the quantifier premodifies the noun, so must be used : I've never seen so much traffic. He has so many friends. / We've got so little time..


On the other hand the expression "a lot" (even though it functions in the same way as a quantifier) is grammatically a noun phrase, literally meaning a "set" or "group". So it is used with such:
There was such a lot of traffic / He has such a lot of friends. / We enjoyed it such a lot.

I hope that's clearer.






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