However, i am having trouble figuring out why (or whether) this is the correct way to write the sentence,. It's not just you that don't know. You would use the present perfect to express something that happened previously, without specifying the time.
I saw this sentence in the book 1q84: Recently one of my friends told me that there is distinct difference between 'know of something' and 'know about something' expressions. Please let me know as soon as you figure it out.
Alright, well, for example, like on saturdays, y’know, what i liked to do. Can it be used in formal conversation/writing? In the first sentence, it seems to me that to know expresses that the speaker experienced the problem/difficulty. I already know how to turn on the television.
I know how to drive a car. Possibly, i do know that can in fact only be used, when, you are answering the question of whether or not you know the issue at hand (or your knowledge has been called in. What is the correct usage of phrase you don't know what you don't know? I know (about) this difficulty/problem.
'know of' is used when you have personal. Why would you have a problem with this?