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to laugh
to smile
to sneer; to ridicule
to be dumbfounded; to be flabbergasted
あの男は他人の失敗を嗤う。
That man laughs at other people's failures.
彼の失敗を嗤うのはよくない。
It's wrong to ridicule his failure.
観客は彼の演説を嗤った。
The audience laughed derisively at his speech.