根据短文内容，用方框中所给单词的适当形式填空，每词限用一次。
Scientists would like to put a huge mirror in space above the earth. It might be sixty miles wide. It would be 小题1:to catch the rays of the sun. it would direct the sun’s rays on the earth as a child might do to make sunlight 小题2: on the wall with a hand mirror.
Why do they want to do this? The sun’s rays could be 小题3: in many ways. They could light up 小题4: by night. The warm rays could stop frosts(霜冻) which might come at night and hurt fruit and crops. They could melt（融化) 小题5: icebergs in the ocean. Perhaps they could change cloud movements and bring rain where it is needed.
