It is known to all that a proper amount of exercise ______ to good health.
Desertification,the name for ______ happens when farmable land is turned into desert,is a growing world problem.
Some students held the view ______ surfing the Internet was good for their study.
It was believed by the ancient Egyptians that intellect was to the mind ___sight was to the body.
Since it is expected that Fed will cut interest rate again, there is no doubt ___the company will make the decision on raising the price of crude oil.
An idea suddenly came to J.K.Rolling ________ she could write a book about people living in the magic world