No, "most unique" is not correct usage. "Unique" means one of a kind, so something is either unique or it is not: there cannot be different degrees of uniqueness, and something cannot be very unique or most unique.
It is not uncommon to hear people say "very unique" or "most unique", but this is not correct. They should be using "unusual" if they want to use it with "very" or "most".
No, it is not proper grammar. The correct phrasing is "you and I."
It is proper grammar.
The proper grammar is "There has come a time." "There" is the subject of the sentence and is singular, hence the correct verb form to use is "has" instead of "have."
It depends on the situation and wording. Not when writing in a formal tone. Example: He got better at playing the piano. He showed improvement in his piano playing.
The unique combination of words, grammar and structure an author employs in a given work is known as the "style."
"She did not have" is the proper grammar.
It is proper grammar to say, "I bet you".
"Don't it" is not proper grammar. The correct form is "doesn't it".
no, that is definitely not proper grammar.
No, it is not proper grammar. The correct phrasing is "you and I."
What was there is proper grammar.
It is proper grammar.
There are many grammar practice websites that will help people learn proper English grammar. These are necessary since many people have no idea what proper grammar is these days.
yes
No
It's you are, you is is not proper grammar.
It's you are, you is is not proper grammar.