--- Your classroom is very clean.--- Sure. It ________ after school every day.
—_____ the population of the U.S.A. in 2005? —It _____ about 296 million. A. What is; is B. What was; was C. How many is; was D. How many was; is
—Does your father still smoke?—No, he has succeeded in _____smoking for three years.
—Where are Jane and her parents?—They _____ Japan.
-----I am going to have a test next week.-----__________!
There were _________ doctors, so Dr Norman Bethune had to work on his own.