Yes, that is a grammatically correct phrase. You might use it as follows: I answer questions as well as possible.
Yes, "best possible" is correct grammar, as in this sentence: This is the best possible outcome considering the circumstances.
No, the phrase "it is well" is not grammatically correct. It seems to be missing a verb or adjective to complete the sentence. You could say "It is well done" to make it grammatically correct.
Both are possible and correct.
The sentence "It lacks agreement Possible correct alternatives are He is the one of the men who does the work or He is one of the men who do the work" are not of correct grammar.
All is well
This is a correct grammar. But it is no possible to cash someone else's SS check.
No, "will be had" is not a correct grammar. The correct grammar would be "will have."
Do you mean: "Are there ways to correct grammar?" Well yes. You see, it's sort of like grading. If someone says something or their grammar incorrect, and you correct them, you are like sort of correcting their grammar and this is the only way to answer your question so.
She plays very well is the correct way to say it.
No, it is correct grammar, not a correct grammar.
Well I think it is
"On a train" is correct grammar.