. I first met Mr Zhao nine years ago. He ____ at a chemical college at that time.
---Are you free after school? ---Sorry, I’ve planned to treat a friend of mine to dinner___for his help.
The old castle is well _____ visiting.
There is no____ that China will be a powerful country in the future.
―I’m too tired. I want to give up.― If you don’t ________, you’ll win in the end.
---What did the Englishman say?---Oh, he asked where ____ .