Written in a hurry , _____________． Which one of the following is right ?

My grandparents asked me to go and see them whenever______

Granny filled the hole ________ oil ________ water in order to put the key into the lock easily.

Must I show you how to play the game?—Oh,thank you.I______how to do it

I want to go to the party, but ______I ought to be studying[ ]