I can't help thinking he knows more than he has told us.

　　我總覺得他沒把他知道的事全告訴我們。

　　The principal knows all the students by name.

　　校長能叫出所有學生的姓名。

　　Everyone knows what's best for him or herself.

　　人人都知道對自己來說什么是最好的。

　　She knows every student in the school.

　　她認識學校里的每一個學生。