He ____ this bike for 600 yuan. Though it was a bit expensive, I think it was reasonable.
Tom as well as two of his friends ________ to the concert last night.
—I am afraid I can’t finish the book within this week.—________.
—It can’t be too worse.—Just _______. Things will turn out to be better so long as you don’t stop trying.
The villagers have already known _________ we’ll do is to rebuild the bridge.
The development of industry has been ________ gradual process throughout ________ human existence, from stone tools to modern technology.