In order to keep fit, the old man makes it a rule _____ for a walk after supper every day.
--How long will you stay there? ---_____.
---I hear you’ve got a set of valuable Australian coins, __ I have a look? ---Yes, certainly.
You’ll have to spend ____ writing your report here.
I wish it __be fine tomorrow.
He bought three books, _____ is in Chinese, ____ in English, and ____ in Japanese.