十万个为什么·科学阅读30篇（2）

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为什么蜂蜜即使存放数千年也不会变质？

Archaeologists have found edible honey in ancient Egyptian tombs dating back over 3,000 years.
Its low water content—usually under 18%—makes it too dry for most microbes to reproduce.
Natural hydrogen peroxide forms slowly in honey when glucose oxidase enzyme reacts with oxygen and glucose.
High acidity (pH 3.2–4.5) further inhibits bacterial and fungal growth inside sealed containers.
Bees also fan nectar with wings to evaporate excess moisture before storing it in combs.
Crystallization does not indicate spoilage but rather a natural physical change in sugar structure.
Even if exposed briefly to air, honey resists contamination better than almost any other food.
Its antimicrobial properties have been used historically for wound dressings and preservation.
Modern labs confirm that spores of harmful bacteria like Clostridium botulinum cannot germinate in pure honey.
However, infants under one year should never consume it because their immature guts lack protective acid barriers.

听 → 读 → 学表达 → 懂 → 今天会说这一句 → 跟读录音 → 自己说一句。

Its antimicrobial properties have been used historically for wound dressings and preservation. 历史上，蜂蜜的抗菌特性曾被用于伤口敷料和食品防腐。
High acidity (pH 3.2–4.5) further inhibits bacterial and fungal growth inside sealed containers. 高酸性（pH值3.2–4.5）进一步抑制密闭容器内细菌和真菌的生长。
Archaeologists have found edible honey in ancient Egyptian tombs dating back over 3,000 years. 考古学家在距今3000多年的古埃及墓葬中发现了可食用的蜂蜜。

这篇中文题目最接近哪一句？为什么蜂蜜即使存放数千年也不会变质？一次学校运动会的通知一份超市购物清单

课文第一句的意思更接近？考古学家在距今3000多年的古埃及墓葬中发现了可食用的蜂蜜。今天学校放假了。请把窗户打开。

这一课主要在讲什么？（看英文标题） Why Does Honey Never Spoil Even After Thousands of Years? How to cook noodles A maths worksheet

Its antimicrobial properties have been used historically for wound dressings and preservation.

Its antimicrobial properties have been used historically for wound dressings and preservation.

第一版：录下来、回听、再听标准音。系统打分以后再加。

用今天的表达，自己说一句。

例子：Its antimicrobial properties have been used historically for wound dressings and preservation.