一个正方形的一边增加2厘米，它的对边减少4厘米，所得到的梯形的上底和下底的比是7

用方框中所给单词的适当形式填空，使短文正确、通顺。（每词限用一次）

how,  either,  be,  danger,  feel,  with,  well ,  lose,  swim,  weather

Summer is coming. The 小题1:_______ becomes hotter and hotter. A lot of people like小题2:_______ in the swimming pools or in the sea. They think water makes them 小题3:______ cool. But some people are not careful enough. They often think they can swim 小题4: ______ than others and they don't have to worry about anything. So these years, many accidents happened and some people小题5:______ their lives(生命). Most of them were students. As we all know, safety is the most important. Do you know 小题6: ______ to protect(保护)yourself? To protect yourself, you must be careful. Remember not to swim in a 小题7:______ place. Don't swim alone, and when you sec a “No Swimming” sign, don't swim, 小题8:_______. Of course, you can swim 小题9: _______ someone who can keep you safe. If you remember these, swimming 小题10:_______ safer.