You should know better than ( to leave ) your little sister at home by herself

题目

You should know better than ( to leave ) your little sister at home by herself
是这样用的吗?know better than to do?

答案

1．know better than+不定式.这种结构意为“不至于”：
She knows better than to go alone on such a night.
在这样的夜晚,她不至于连不宜单独外出也不知道.
know better than to do sth.的含义是be wiser,better informed,or more
sensible than to do or believe sth.
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