过去式: knew
过去分词: known
第三人称单数: knows
现在分词: knowing
I don\'t know what to make of the new manager.
这位新经理,我不知道怎么评价他才好。
These problems are all in your mind, you know.
你知道,这些问题都只是你的凭空想象而已。
You\'ll like her once you get to know her.
你一旦了解了她就会喜欢她的。