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awhile, a while, while

Do not confuse the adverb awhile with the noun phrase a while:
            awhile (adverb):                        We stood awhile on the dock; awhile back.
            a while (article and noun):      We stood for a while on the dock; a while ago; wait a while.

At the beginning of sentences, while may be used in place of though, although, or whereas:
While most Canadians speak English, Québécois speak French.