As is known to us, theory is based on practice and servers practice.A. by chance B. in turn C. in return C. by turn
The new library building _____ last week.
—Did you call Sara back? —I didn’t need to, _____ we’ll have a meeting together tonight.
Keep practicing and you _____ your English.
The air in mountain areas is ____ that in big cities.
Beijing is _____ capital of China and it is _____ city with many places of interest.