“A lot of” + noun means a large quantity or a high number. “A lot of” can be used with both countable and uncountable nouns.
Verb + “a lot” means “very much” or “frequently”:
I like this singer a lot.
= I like this singer very much.
She travels a lot for work.
= She travels frequently for work.
“So” is used with “that” to add extra information – usually a result or consequence:
Last night I was very tired.
Last night I was so tired that I almost fell asleep while driving.
This book is very interesting.
This book is so interesting that I stayed up until 3 AM reading it!
She plays the piano very well.
She plays the piano so well that people often ask if she’s a professional.
Last night I was a lot tired.
In informal spoken English, it’s common to use “really” instead of “very”:
However, you can’t substitute “really” for “so.”
Also, in informal spoken English some people use “so” without adding extra information, particularly when making an exclamation:
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