有一种爱是最无私的，它是温暖的太阳，奉献着七色光芒；是辽阔的海洋，袒露着宽广胸怀；是肥沃的土壤，哺育儿女茁壮成长……它是（   ）

有一盛水的圆柱形敞口容器，水面的升降可由进水管和出水管调节．在其右侧某一高度朝确定方向射出一激光束，在容器底部中央产生一个光斑，如图所示，该光斑（　　）

阅读诗歌回答后面小题。
                                                                                                              跌 倒
                                                                                                              牧 也
                                                                                                       风，跌倒了
                                                                                                      才有了美丽的落叶
                                                                                                      云，跌倒了
                                                                                                      才有了滋润大地的雨水
                                                                                                       所以
                                                                                                       我们不再害怕跌倒
                                                                                                       让我们在跌倒时
                                                                                                       用最美丽的姿势
                                                                                                        站起来

How does the boy go to school?

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