给出下列判断：①在数轴上，原点两旁的两个点所表示的数都是互为相反数；②任何正数必定大于它的倒数；③5ab， $\frac{x}{2}$ +1， $\frac{a}{4}$都是整式；④x²-xy+y²是按字母y的升幂排列的多项式，其中判断正确的是（　　）​

    Do you like sunny days or rainy days? Some people like fine days, because they can go out to do what they like. They may ____ the bright sunshine, or wear colourful swimming clothes to swim in the ____. They may also like to take their____ to take beautiful photos. It is pleasant weather. They don`t like rain. They always ____sad when it rains. I like sunshine very much, but I enjoy rain as well.

    On ____ days, it is wet. I like to listen to music, or listen to people joke on the radio. It is____ a great thing to take an umbrella to stand out and listen to the sound of the rain. You can feel the cool weather and it is comfortable, ____ in summer or autumn.

    Sunshine is bright and rain can make people quiet. Which do you like ____? I hope you can have a good time no matter（无论）it`s sunny or rainy.

一物体静止在水平地面上，现给物体施加一竖直向上的拉力作用，不计空气阻力，物体机械能E与物体升高的高度h之间的关系图象如图所示，其中图线在A点处的切线的斜率最大，在B点处的切线水平，h₂～h₃的图线为平行于横轴的直线，则下列说法正确的是（   ）