根据短文内容完成下列各题

    Today l would like to tell you about my dream．

    My dream is a simple but great one．It is to be a teacher．①我从小就梦想做一名老师!②First of all，it is a pleasure for me to be with children．They make me feel ③ happy and young．Furthermore，teachers play an important part in the development of children．They teach children and show them how to be good．When children grow up，they use the knowledge that they have learned to develop their motherland and make it beautiful. I think teaching is one of the ④    (value) things in the world．

    That’s all．Thank you !

如图所示是奥斯特实验的示意图，实验中导体中有电流通过时小磁针发生偏转，根据此现象可得出结论： ____．如果移走小磁针，该结论 ____（成立/不成立）

25℃时,将稀氨水逐滴加入稀盐酸中，当溶液的pH＝7时，下列关系不正确的是（     ）

如图，在平面直角坐标系xOy中，抛物线W的函数表达式为y=-x²+2x+3，抛物线W与x轴交于A、B两点（点A在点B的右侧），与y轴交于点C，它的顶点为D，直线l经过A、C两点．