--Please sit down. --______.
—What are these?—They’re _______ and _______.
—What were you doing at this time yesterday?—We _______ in the classroom.
—Must we finish the project in a month?—No, you _______.
—Which is _______, the sun, the moon or the earth?—Of course the sun.
—How many students are there in your school?—_______ students, I think.