13.About 90 percent of the equipment presented by the administration,as well as the facilities of our own, ______made good use of in teaching.
I'd like to start my own business—that's ________ I'd do if I had the money.(2011·江西)
Scientists study ________ human brains work to make computers.
We promise ________ attends the party a chance to have a photo taken with the movie star.
The newcomer went to the library the other day and searched for ________ he could find about Mark Twain.
His writing is so confusing that it's difficult to make out ________ it is he is trying to express.(2011·安徽)