I have confusion about the following sentence.
Sue enjoys her work. She wouldn't do it if she not enjoyed it.
Sue enjoys her work. She wouldn't do it if she didn't enjoy it.
Which one is correct?
In English, there are two rules for how to state the negative of a verb.
"Not" comes after the verb.
Correct: "I am not at home."
Incorrect: "I not am at home."
Except for a few cases, you must rephrase to use the auxiliary verb "do".
Correct: "She does not eat meat." (from "She eats meat" -> "She does eat meat")
Incorrect: "She eats not meat."
"She not enjoyed it" is wrong on both of these rules. "She did not enjoy it" (shortened to "She didn't enjoy it") is correct.
Sue enjoys her work. She wouldn't do it if she not enjoyed it. - Sounds grammatically incorrect
Sue enjoys her work. She wouldn't do it if she didn't enjoy it. - This one is correct.
I like my job. I wouldn't have done it for four years if i had not liked it. I like my job. I wouldn't do it if i didn't like it.
And FYI - your title of the question contains grammatical error.
It should be - Is this a correct sentence ? OR Is it a correct sentence ? OR Which one of the following is the correct sentence ?