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为何海洋潮汐每天涨落两次而非像河流那样单向流动

Tides happen because the Moon’s gravity pulls Earth’s oceans toward it more strongly than the land.
At the same time, inertia creates a second bulge on the opposite side of Earth.
As Earth rotates once every 24 hours, most coastlines pass through both bulges daily.
That’s why many places see two high tides and two low tides within about 25 hours.
The Sun also affects tides, but its pull is only half as strong as the Moon’s.
When Sun and Moon align, we get spring tides — higher highs and lower lows.
When they sit at right angles, neap tides occur with smaller differences between levels.
Coastal shape and ocean depth change local tide timing and height significantly.
Some bays, like the Bay of Fundy, amplify tides so much that water rises over 15 meters.
Tide clocks and satellite data help ships plan safe entry and exit from ports.

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

Coastal shape and ocean depth change local tide timing and height significantly. 海岸形状和海水深度会显著改变当地潮汐的时间和高度。
As Earth rotates once every 24 hours, most coastlines pass through both bulges daily. 地球每24小时自转一周，大多数海岸线每天都会经过这两个隆起。
When they sit at right angles, neap tides occur with smaller differences between levels. 当二者呈直角排列时，则出现小潮，潮差变小。

这篇中文题目最接近哪一句？为何海洋潮汐每天涨落两次而非像河流那样单向流动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？潮汐的产生是因为月球引力对地球海洋的拉力强于对陆地的拉力。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 Ocean Tides Rise and Fall Twice Daily — Not Once Like River Currents How to cook noodles A maths worksheet

Coastal shape and ocean depth change local tide timing and height significantly.

Coastal shape and ocean depth change local tide timing and height significantly.

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：Coastal shape and ocean depth change local tide timing and height significantly.