I think you should complain, , of course, you are happy with the situation.
We aren’t sure of the weather. We _______ sightseeing unless it_________ tomorrow.
Jim, _______do you know about table manners all over the world?
The old lady is so weak. She________by her relatives.
Behind the department store there used to ______ much waste, _______?
It is convenient for people to work by subway. It’s said that The Line 4 subway in Chengdu _______by the time of 2018.