第四部分写作（共两节，满分20分） 第一节短文改错（共10小题，满分5分） In order to go diving, you need some equipments. First divers carry their backs a metal bottle, which is filled of water. There’s enough air in it to last about 40 minutes. Next, divers carry heavy metal weights in a belt around its bodies. With these heavy weights they would float to the surface.  You see, there are a lot of air in their air bottles, and this will bring them up to the surface if they didn’t have any more weights. Mostly divers don’t go very deep. 76_______ 77_______ 78_______ 79_______ 80_______ 81_______ 82_______ 83_______ 84_______ 85_______