Yes, you can. Example: Bob is not a human. Therefore, Bob is considered an alien.
No, it's not improper.
Therefore, because it is not improper, one may begin a sentence with "therefore."
And is a coordinating conjunction; therefore it should never begin a sentence. Ironically, though, the preceding sentence is correct because and is used as a word, not as a conjunction.
The word 'is' can begin a sentence but not be a question when it is the subject of the question. Example sentence - Is can be the subject in a sentence. But only in sentences of that type (above) or, 'Is' is a two letter word. Otherwise is cannot begin a sentence.
Yes. There is no word that cannot begin an English sentence.
The word 'therefore' is a connector, so no.My cell phone is thin and light and therefore very convenient to carry around.You returned the book two weeks after it was due; therefore, you will be charged a late fee.
It is possible to have a sentence with the word it at the beginning, as this sentence proves.
yes you can
Never
Of course you can. There is no word in English that cannot begin a sentence.
Therefore, instead of turning at Faber Street, she crossed it.
Yes, you can begin a sentence with the word "or" when presenting options or alternatives. For example, "Or you can choose to study abroad for a semester."