Though he started late,Mr.Guo played the piano as well as,if______,Miss Liu.
Boris has brains. In fact, I doubt whether anyone in the class has___IQ.
Jumping out of_____airplane at ten thousand feet is quite_____exciting experience.
The warmth of___sweater will of course be determined by the sort of___wool used.
Paper money was in___use in China when Marco Polo visited the country in___thirteenth century.
Professor White has written some short stories, but he is___known for his plays.