Tom ______ half an hour doing his homework and listening to pop music ______him 20 minutes.
—What did our geography teacher say?—She told us that the earth _____ around the sun.
—Lily, _____ you _____ your ticket?—Not yet!
We couldn’t wait _______ a good rest after the exam.
Although we’ve learned English for years, we have trouble _____ the foreigners.
-----How many students are there in the classroom?------_______.