生活中很多平凡的小事能体现个人对社会、对人生的态度。下列行为中，值得我们学习的是（    ）

小星同学为实验室设计了一个多档位电加热器，其工作原理图如图6所示。其中R₁、R₂、R₃为发热电阻，三个灯泡为上述发热电阻相应的的工作指示灯，其所消耗的电功率可忽略不计。小星设想通过开关的组合，使电加热器能有多档功率。当只S1闭合时，测得功率为200W；当只S₂闭合时，测得功率为100W；小星设计此电热器最大发热功率为800W，则：

    One day, a little schoolboy went home with a pain in his stomach.

    "Well, sit down and 1 a cake," said his mother."Your stomach 2hurting because it's empty.It'll be all right when you've got something in it."

    Five minutes later, Dad came home 3 the office.And he said he had a headache.

    "That's because your head is 4," said his clever son."You'll be all right if you have got 5 in it." His dad and mum laughed.