No, although it has a subject, it is missing a time element and a location, which all sentences require to be actual sentences.
Your question is not grammatically correct and is not clear.
To be clear, one's answer should be grammatically correct.
Yes, the sentence "I did not hide the keys" is grammatically correct.
The sentence given is grammatically correct. The verb in in its imperative mood and therefore does not need an explicit subject; the subject "you" is presumed.
Yes, the phrase "I came home at about one o'clock" is grammatically correct. It follows a subject-verb-object structure and conveys a clear message about the time of arrival.
"there come"
Absolutely. Why would you think it might be incorrect?
Yes, "please sign in the space provided" is grammatically correct. It is a polite and clear way to instruct someone to sign in a designated area.
A grammatically correct sentence follows the rules of syntax and grammar in a specific language. This includes using proper word order, punctuation, verb tense, subject-verb agreement, and sentence structure. Grammatically correct sentences are clear, coherent, and convey the intended meaning effectively.
"Not like that" can be grammatically correct, depending on the context.
Yes! That is grammatically correct!
Yes, 'for free', is grammatically correct.