- 你知不知道他们是谁?
Do you know who they are?
- 谁都知道知足常乐。
Everybody knows that happiness is in contentment.
- 她问我知不知道他的地址。
She asked me if I knew his address.
- 我知道他的名字，但不知道他长什么样。
I know him by name, but not by sight.
- 玛莉亚既不知道他的名字，也不知道他的电话号码。
Maria knew neither his name nor his phone number.
- 我该通知谁？
Whom should I inform?
- 你知道现在几点吗？
Do you know what the time is?
- 她知道您的电话号码吗？
Does she know your telephone number?
- 谁知道？
Who knows?
- 我对这个计划一无所知。
I am quite ignorant of the plan.
