Why does the author mention the experiment in the third paragraph?

为什么作者在第三段提到那个实验？

同一单元的其他句子

• The main idea of the passage is often stated in the first paragraph.文章的主旨通常在第一段中陈述。
• Skimming helps readers get a general overview of the text quickly.略读帮助读者快速了解文本的大致内容。
• Can you infer the author's attitude from the tone of the article?你能从文章的语气推断出作者的态度吗？
• Pay attention to transition words to understand the logical flow.注意过渡词以理解逻辑流程。
• Don't look up every unfamiliar word while reading; use context clues.阅读时不要查每个生词，要利用上下文线索。