Is `一緒に` needed in this case？

> **A:** 買い物へ行きたい。
>
> **B:** そう。
>
> **A:** 一緒に行きましょうか？

Or is it just ->> `行こう`？
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2012-01-31T08:40:18.427
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2012-01-31T10:10:39.587
2020-06-17T08:18:27.500
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grammar syntax
Is 一緒に needed in this case?
I think「一緒に」is necessary, but it will be better to say 「一緒に行きませんか」( if Aーさん
isn't close to Bーさん) or「一緒に行かない？」( if B-さん is a friend). It's more polite.
CC BY-SA 3.0
2012-01-31T10:10:39.587
4505
2012-01-31T10:10:39.587
1024
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