An year is not correct grammatically. An is only used before a vowel. Year begins with a Y so one would write 'a year'. But an apple; an egg, an institute, an opening, an umbrella. However if a U is pronounced 'yu' as in 'use' or 'Ugandan' then one uses 'a'. A useful thing. A Ugandan man.
No it isn't a grammatically correct word.
Grammatically
no
Yes, "evidenced" is a grammatically correct word. It is the past tense of the verb "evidence," meaning to show or prove something.
The word not is an adverb. It is a word expressing denial, negation or refusal
True
Yes, the sentence is grammatically correct.
a pronoun
The correct spelling of the word "grammatically" is G-R-A-M-M-A-T-I-C-A-L-L-Y.
Yes, it is grammatically correct to end a sentence with the word "so." However, it may be informal or conversational in style.
Neither really. 'In' would be the word to use.
Yes, it is.