Well, it's really sort of difficult to explain.
Starting a sentence with "for" is not necessarily improper, but it may make the sentence sound more formal or structured. It can be used to introduce a reason or explanation in the sentence. However, overusing it may affect the flow of the writing.
this is not an improper sentence.
You can, but it is considered improper grammar. Teachers don't like it when you do.
Well, you can, but it would be improper English. :)
No, it's not improper.
Understand the definition - improper means not proper. Then make a sentence When that kid sneezed, it was improper of him to not cover his mouth
It was quite improper for you to ask such a question.
Therefore, because it is not improper, one may begin a sentence with "therefore."
"That was improper behavior" "Its quite improper to invite your self over"
I hope this is not an improper answer. Is this suit improper for the dance? Was the response improper?
Well, it's technically improper to place a conjunction at the start of a sentence, though this rule is often ignored in casual conversation. For example: 'And he jumped.' OR 'But he never did it.' are improper. Also, every conjunction needs a phrase on either side. For example: 'He threw a fastball and.' is incorrect. You need another phrase, or else people will end up saying 'AND WHAT???"
No, it's not improper.