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为什么雪花总是六边形，却从不会是二边或五边形？

Snowflakes form when water vapor freezes directly onto tiny dust particles in cold clouds.
Water molecules arrange themselves in a hexagonal crystal lattice due to hydrogen bonding angles.
Each molecule bonds at precisely 120 degrees, naturally favoring six-fold symmetry.
Even tiny temperature or humidity changes alter branch growth but preserve the six-arm pattern.
No known natural ice crystal forms with two, five, or seven sides under Earth conditions.
Scientists have created pentagonal ice in labs using special substrates—but it’s unstable and melts instantly.
This consistency helps meteorologists classify snow types and predict storm behavior.
Photographing individual flakes reveals infinite variation within the rigid six-fold rule.
Computer models simulate how vapor diffusion shapes each arm independently yet symmetrically.
That universal geometry reflects deep physical laws—not random chance or design.

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

Each molecule bonds at precisely 120 degrees, naturally favoring six-fold symmetry. 每个分子以精确的120度键合，天然趋向六重对称。
This consistency helps meteorologists classify snow types and predict storm behavior. 这种一致性有助于气象学家分类雪型并预测风暴行为。
Photographing individual flakes reveals infinite variation within the rigid six-fold rule. 拍摄单个雪花可发现，在严格的六重对称规则下存在无穷变化。

这篇中文题目最接近哪一句？为什么雪花总是六边形，却从不会是二边或五边形？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？雪花在寒冷云层中，水蒸气直接冻结于微小尘埃颗粒上而形成。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 Do Snowflakes Always Have Six Sides—But Never Two or Five? How to cook noodles A maths worksheet

Each molecule bonds at precisely 120 degrees, naturally favoring six-fold symmetry.

Each molecule bonds at precisely 120 degrees, naturally favoring six-fold symmetry.

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：Each molecule bonds at precisely 120 degrees, naturally favoring six-fold symmetry.