We all know that learning a foreign language _______ time and effort.
The price of this camera is quite _____ . I don’t have enough money to buy it.
---How do you study English? --- _____ watching English movies.
My brother has ___ come here, but my sister hasn’t ____.
—I have many books to read these days. —Me, too.
—Dad, can I go out? —Yes, but please be careful not to play on the street when there are too many cars.