China’s economic and social development requires more substantial reforms, as unnecessary government influence on the private sector has _______ an abuse of authority.
The traditional view is ______ we sleep because our brain is “programmed” to make us do so.
______ he referred to in his article was unknown to the general reader.
____ matters most in learning English is enough practice.
I just wonder __________ that makes him so excited.
Engines are to machines _________ hearts are to animals.