As preparation for my trip, I am re-learning my Japanese. I imagined a
scenario which I am not sure if it is okay to ask.

Is it polite to ask someone if they speak English or are people offended by
the question?

Also, is 英語を話せますか okay or is 英語ができますか better?
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2015-02-02T07:38:58.023
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politeness culture
Is it polite in Japan to ask if someone speaks English? (英語を話せますか？)
either is fine. no problem both "英語を話せますか" and "英語ができますか".  
But, I would use "あなたは英語を話せますか？".  
because,  
"話せますか" include the meaning of "speaking".  
"できますか" include the meaning of "speaking" and "writing" and "reading"...etc
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2015-02-02T08:07:46.793
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While I wouldn't consider it too impolite to ask someone directly whether he
or she speaks English, the better strategy might be to ask

> 英語で質問してもいいですか  
>  お伺いしたいんですが、英語で大丈夫ですか

or something along these lines. This way, you are asking for permission to
speak in English without putting anyone in the situation of assessing their
own English skills.
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2015-02-02T08:32:54.900
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I often say 英語は大丈夫ですか? to shop keeper telling them I will be the one to speak
English and it is ok most of the time. (They will often become reluctant and
answer ちょっと.. though)
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2015-02-02T08:54:31.450
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