laughed後面加什麼介詞

加介詞at，為固定詞綴搭配，中文意思是嘲笑因……而發笑

She knew that the girls used to imitate her and laugh at her behind her back.她知道那些女孩子過去常在背地裏模仿她、嘲笑她。

When I was a lad his age I would laugh at the strangest things.

我是他那麼大的小夥子時，我常嘲笑一些最奇怪的事情。