—What shall I do with the medicine? —The instructions _______ that you should take three pills a day.
He ____ his home for a week.
--What’s ___ population of China? --China has ____ population of 1.5 billion.
--what do you think of the film? ---_____?
Is ____ dangerous to swim in the river alone?
--___do you clean the reading room? ---Every two or three days.