呼吸是动物重要的生理特征．不同的动物呼吸的结构或器官差异很大，但其功能都是最大限度的吸收O₂，排出CO₂．回顾你的实验过程，回答下列问题：

    William Henry Harrison, the ninth President of the USA, was born in a small town. When he was a boy, he was very quiet and shy. Because he was so quiet, everyone thought that he wasn't bright. People in the town often put a nickel(五分镍币)and a dime(十分硬币)before him and asked him which to choose. He always chose the nickel and they laughed.

    One day a woman felt sorry for him. She asked, "Why do you never take a dime and always choose a nickel? Do you know a nickel is worth(值……钱) much less than a dime?"

    "Certainly I know it.” William answered slowly. "But if I choose the dime, they will not ask me to choose them any more.”

请模仿下面句子的形式，从“鲜花”、“矿石”、“蜡烛”、“航船”等事物中选择两个作为陈述对象，写两组句子。也可自选其他事物来写。要突出所写对象的特征。

例句：种子，如果害怕埋没，那它永远不能发芽。

一台小型发电机产生的电动势随时间变化的正弦规律图象如图甲所示．电路组成如图乙所示，已知发电机线圈内阻为5.0Ω，外接灯泡阻值为95.0Ω，灯泡正常发光，则（   ）