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 experience with wha...
Know in (1) refers to the clause that comes right before it, so there's no pronoun necessary -- it's essentially a transform of I know it's your job. In (2), however, the object of know is not indicated, as you point out, so something must be provided.
Why do you think that He doesn't know him from his schooldays means that he does know him? It would only have that sense if you added something like In fact, he first met him at university.
For me, know implies knowledge of details or individual pieces, while am aware of implies a knowledge only of a whole. Using your example, knowing my rights means that I know I have the right to remain silent, the right to be represented by an attorney, etc. Being aware of my rights might mean the same thing, but implies that I know that I do have rights, but am not sure what those rights are.
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 to question, and you are answering that challenge). Let's say "out of the blue" you wanted to state that "you know that" -- and you wanted an emphatic version.
In my understanding, ' as we know it ' usually follows a noun phrase and means like The building as we know it = the version/condition of the building we know now. First, I'm not sure about its grammar. Is the 'as' a conjunction? Is it correct to think that 'it' changes to 'them'? E.g., the buildings as we know them Second, a question about its use. Is it possible to use when the preceding ...
Therefore, saying "did you know" asks if you have previously known something. "Do" is the present tense, so saying "do you know" would ask if you currently know.
Thus, "As far as I know, Bob is happy" over "Bob is happy, so far as I know". They are equivalent in meaning therefore, but choice of one over another betrays, for me, certain prejudices. I also sense that "so far as" sounds slightly antiquated and is losing ground.
