-Are you good dancing ?-Yes, I dance very .
—Which is _______, the sun, the moon or the earth?—Of course the sun.
—How many students are there in your school?—_______ students, I think.
—Would you mind my smoking here?—_______ It’s not allowed here.
—_______ do you have a sports meet at your school?—Once a year.
The old man was _______ sad _______ say a word when he heard the bad news.