Of course you know, you finished school.

 Your parents might say that while you are doing your homework.

They always say "oh its easy!", or "come on you know the answer, you're just not thinking!". Don't you hate that? They always say that. You know you're thinking, but you can't say that. You can't talk back.

Your parents think they know everything. Sometimes they get the answers wrong and they love to say" oh, so your calling me a liar?".

That's way different than knowing everything. your parents also say,"come on, at your age,I was doing this, that and the other thing."

Then they always tell you things you already know what or how to do.