I know (about) this difficulty/problem. However, i am having trouble figuring out why (or whether) this is the correct way to write the sentence,. 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.
Recently one of my friends told me that there is distinct difference between 'know of something' and 'know about something' expressions. 'know of' is used when you have personal. 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 already know how to turn on the television. Can it be used in formal conversation/writing? Please let me know as soon as you figure it out.
In the first sentence, it seems to me that to know expresses that the speaker experienced the problem/difficulty. What is the correct usage of phrase you don't know what you don't know? I saw this sentence in the book 1q84: In (2), however, the object of.
Alright, well, for example, like on saturdays, y’know, what i liked to do. I know how to drive a car.