阅读理解

    The reality show(真人秀节目) "Where are we going, Dad?" becomes a hit show on TV these days. This TV show is about dads and children who are from five different families. They will complete some hard tasks without moms in three days and two nights. The five dads have to play the roles of "dad" and "mom" at the same time. All of the five dads are famous people and they must forget their popularity but do as a normal father. The cell and toys aren't allowed to use in the show. They have to live in a very tough environment. At first, all the five children cry. After all, they are just 4-6 years old. They never experience life in the countryside. But later they are all used to this kind of exciting life with their father.

    Among the five star kids, four-year-old Kimi impresses people most. During the TV show, Kimi is well-behaved, never shouts at others and always listens to his father, Jimmy.

    "The whole experience teaches him a lot," Jimmy says. "He now knows how to behave well in public and how to be patient."

    Jimmy's soft parenting skills, Kimi's cute face and their warm interaction on the show win many viewers' hearts.

工厂里经常使用静电除尘技术，用一块带电的金属板，把浮尘吸附在金属板上．静电除尘的原理是____ 

呼吸时，体内进行气体交换的原理是（　　）

图中，两块平面镜成90°放置，画出图示光线经两次反射的光路图(保留作图痕迹).

课内阅读《黄河是怎样变化的》。
    黄河是世界上含沙量最大的大河，其含沙量相当于长江的68倍。黄河每年从中上游带到下游的泥沙总重量达16亿吨，其中12亿吨被搬到了大海，4亿吨则沉积在下游河道中。问题出在这4亿吨泥沙上。它使黄河的河床逐年升高，结果有的河段高出两岸农田3～4米，甚至高出10米以上，使黄河成了悬河。每到洪水季节，黄河这些地段的堤坝很容易决口，造成可怕的大水灾。