均衡营养、合理用药可以保障身体健康．

①维生素C能与I₂、Fe³⁺等发生反应，说明维生素C具有 ____（填“氧化”或“还原”）性；强酸、强碱对皮肤具有腐蚀作用，是因为蛋白质遇强酸、强碱会发生 ____（填“盐析”或“变性”）．

②某复方氢氧化铝片说明书（部分）如下：

【药品名称】复方氢氧化铝片

【主要成分】本品每片含氢氧化铝0.24g、三硅酸镁0.105g、颠茄流浸膏0.002 6mL

该药物可用于治疗 ____；

请写出任意一个相关的离子方程式： ____

热机是将燃料燃烧产生的内能转化为 ____能的装置，在内燃机的一个工作循环中，活塞向下运动的冲程有 ____个．

阅读理解

     Mr. Lee was in bed and was trying to go to sleep when he heard the bell ring. He turned on the light and looked at his clock. It was twelve o'clock. "Who can it be at this time of night?” He thought. He decided to go and find out. So he got up, put on his dressing gown(长袍) and went to the door. When he opened the door, there was nobody there. "That is very strange." Then he went back to his bedroom, took off his dressing gown, got back into bed, turned off the light and tried to go to sleep.

     A few minutes later he heard the bell ring again. Mr. Lee jumped out of bed very quickly and rushed to the door. He opened it, but again he found no one there. He closed the door and tried not to feel angry. Then he saw a piece of paper on the floor. He picked it up. There were some words on it: "It is now after midnight (午夜), so it is April Fool's Day(愚人节). April fool to you!”

    “Oh, it was the English boy next door!" Mr. Lee exclaimed（惊叫）and almost smiled. He went back to bed and fell asleep at once. The bell did not ring again.