STEM与日常科技·英语30篇（7）

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运动传感器如何在黄昏时自动点亮路灯

Streetlights now turn on automatically when motion sensors detect movement.
These sensors use infrared technology to sense heat changes from passing people or cars.
They also rely on ambient light levels to decide whether it is truly dusk.
A built-in photocell measures surrounding brightness and activates the system only in low light.
Once triggered, the sensor sends a signal to the lamp’s control circuit within milliseconds.
This avoids unnecessary energy use during daylight or when no one is nearby.
Modern versions combine motion detection with timers to extend lighting only for short durations.
Engineers design them to ignore small animals while responding reliably to humans.
The entire process requires less than five watts of standby power per unit.
This smart automation helps cities cut electricity use by up to thirty percent.

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

Streetlights now turn on automatically when motion sensors detect movement. 路灯现在通过运动传感器检测到移动时会自动开启。
Engineers design them to ignore small animals while responding reliably to humans. 工程师设计时使其能忽略小型动物，同时对人类可靠响应。
This avoids unnecessary energy use during daylight or when no one is nearby. 这避免了白天或附近无人时的不必要耗电。

这篇中文题目最接近哪一句？运动传感器如何在黄昏时自动点亮路灯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？路灯现在通过运动传感器检测到移动时会自动开启。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） How Motion Sensors Trigger Streetlights at Dusk How to cook noodles A maths worksheet

Streetlights now turn on automatically when motion sensors detect movement.

Streetlights now turn on automatically when motion sensors detect movement.

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：Streetlights now turn on automatically when motion sensors detect movement.