"что ты знаешь о предложном падеже?"

Hello!!
Сегoдня пагода oчень хорошо!!
I need some help with this,if you would be so kind.

"Вы не видели моя учебник"....Vwi ne vedyel m-oya ooch-yeb-nik?"
Have I pronounced this correct..How would you do say it?
I think it means "Have you seen my texbook?"

А тохе не знаю это урок....

"что ты знаешь о предложном падеже?"
Is this "what would you know about..." and then "предложном падеже"--what does this mean,and how is it pronounced?

Thanks again for your patience everybody,Im trying hard...it just seems to keep "falling" out of my head when I go to sleep..lol
JD

Сегодня очень хорошая погода!!
-- Corrected

Вы не видели мой учебник?
-- Corrected (the accusative http://masterrussian.com/aa071200a.shtml)

Что ты знаешь о предложном падеже?
Is this "what would you know about..."
-- What do you know about...

and then "предложном падеже"--what does this mean,and how is it pronounced?
-- The prepositional

Surely you mean the prepositional?

Yes, the prepositional, of course.