I care about most is whether the company provides opportunities for further education

I don’t know ______ or not the books _____ to the homeless children next month are really useful

Michael Jordan has failed over and over again in hislife. And that is _______ he succeeds.

I think students may bring iPad to school.–_________ This can cause some trouble.

when shall we go to visit my grandpa—Grandpa is very busy at present．We’ll go to see him whenever__________.