1 . When we begin to see things differently around us, we can open __________ (us) up to new possibilities and new opportunities and clear out fear. (所给词的适当形式填空)

3 . He practiced rapidly moving the glove to his good hand after he had pitched the ball to his father. He was always forcing __________ (he) to get that glove faster and faster. (所给词的适当形式填空)

4 . The middle route, the most prominent one due to __________ (it) role in feeding water to the nation’s capital, begins at the Danjiangkou reservoir in the Hanjiang River in central province of Hubei and runs northeastward to Beijing and Tianjin. It started supplying water in December 2014. (所给词的适当形式填空)

5 . As larger groups of people began living together in towns and cities, these populations needed reliable sources of clean water, a network of streets for trade and a way to defend __________ (they) against unfriendly neighbors. (所给词的适当形式填空)