YOU SAID:

Probably too quiet and polite for them but you never know.

INTO JAPANESE

おそらく彼らのためにあまりにも静かで礼儀正しいが、あなたは決して知らない。

BACK INTO ENGLISH

Probably too quiet and polite for them, but you never know.

INTO JAPANESE

おそらく彼らのためにあまりにも静かで礼儀正しいですが、あなたは決して知りません。

BACK INTO ENGLISH

Probably too quiet and polite for them, but you never know.