A few days ago, I read this sentence in "English grammar in use" by Raymond Murphy:

We don't know where we're going for our holiday yet.

I thought present perfect must be used here as: we haven't known...yet. But when I searched on the internet, everyone says that I can not use present perfect "I haven't known" here.

Can someone please explain this to me?

1 Answer 1


It seems you misunderstand the meaning of know. It does not describe an action that you perform, but rather a state you are in. You cannot perform the action of knowing something at a specific moment.

You can, however, find out or discover something. From that moment on, you know that something.

You could rephrase your sentence with a present perfect:

We haven't decided where we're going for our holiday yet.

The difference between decide and know is that decide describes an action, so you can talk about it as an action, whereas know is a static verb, which does not describe an action.

Ok, there is actually a case where know can describe an action, the so-called "biblical" sense, i.e. have sexual relations with someone. But a sentence like I haven't known her yet will seem very strange to modern speakers!

  • 2
    I haven't known the combination to that safe since 1985.
    – Davo
    Commented Dec 20, 2017 at 12:38
  • 2
    @Davo good one! If there is any confusion left from the OP I might add some more detail. For now, I have proposed for the question to be moved to ELL, where I think it is a better fit.
    – oerkelens
    Commented Dec 20, 2017 at 12:39
  • I haven't known him since 2015, only since 2016 Commented Dec 20, 2017 at 16:30

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