I know these two common contractions:
I'll enjoy it
I won't enjoy it
I wonder: can one use the first one with a negative?
I'll not enjoy it.
Is this correct?
If so, when/how would one use it? Would it differ from "I won't" semantically?
"I'll not enjoy it" isn't incorrect, but it sounds a bit stilted or old-fashioned.
"I won't enjoy it" is the form more usually heard.
Either one should be understood to have the same meaning.
Technically, the two are the same. I'll not and I won't both expand to I will not. In modern day, the first contraction is less seen, but that does not mean that it is not correct grammatically.