However – English editing.

An adverb with two main uses:
 To modify an adjective or another adverb:
We cannot afford to postpone necessary actions, however difficult, in the future.
 As a sentence adverbial or conjunction:
There was, however, one important difference.
This is the traditional way to use the word, enclosed between commas, as here. It can also be placed at the beginning of the sentence:
However, they may not need a bus much longer.
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