Yes, 'for free', is grammatically correct.
The phrase "how don't I" is not grammatically correct. A more correct way to phrase it would be "why don't I."
"For free' is grammatically correct. It is an idiom of the English language.
This is not grammatically correct. The correct form is 'you do not know', or the abbreviated 'you don't know'.
Yes
The phrase "Is you don't miss me do you" is not grammatically correct. It should be rephrased to something like "Don't you miss me?" to be correct.
The phrase "had already left" is grammatically correct. The phrase "had already been gone" is not grammatically correct.
yes, it is
No, it is not grammatically correct to say "keep stick to." The correct phrase would be "keep sticking to" or "stick to."
Yes. It is a noun phrase.
The correct phrase is "that was you," as the verb "was" agrees with the singular subject "you."
Yes, it is grammatically correct. "Part and parcel" is a phrase that originated as a legal term in the fifteenth century. It means an essential or integral part.
No, it's not grammatically correct. Try this: She wished she had ran instead of marrying him.