I think comments like the ones described in this thread are often taken the wrong way, but there are some that can't be seen any other way than displaying either (a) a considerable degree of ignorance, or (b) a very patronizing manner, such as お箸使えるの?すご〜〜〜い! when nearly every civilized person in the world can use chopsticks, or うわ� � 。日本語上手!from a new acquaintance, when all you've uttered is はじめまして.
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