初中英语阅读背单词-智能手表如何监测心率数据?

A smartwatch has a tiny sensor on its back. It shines green light against your wrist skin. Blood vessels under your wrist expand and shrink each time your heart pumps blood. The sensor catches these small changes of blood flow.

智能手表的背面装有一枚微型传感器。它向你的手腕皮肤射出绿光。每当心脏泵血，手腕下的血管就会扩张、收缩，传感器便能精准捕捉到血流的细微变化。

You may wonder why it uses green light instead of other colors. Green light gets absorbed well by blood. When blood flows faster, less green light bounces back to the sensor. The watch can calculate heart beats per minute from these light signals.

你可能会好奇，为什么智能手表偏爱用绿光检测心率。绿光极易被血液吸收，当血流速度加快时，反射回传感器的绿光就会减少。手表依靠这些光信号变化，计算出我们每分钟的心跳次数。

The watch keeps checking your heart rate all day long. It works continuously when you walk, run, exercise or rest. It can record your real-time heart rate, highest heart rate and resting heart rate.

智能手表可以全天候监测心率。无论是走路、跑步、运动还是休息，它都在持续工作，实时记录你的即时心率、最高心率和静息心率。

However, smartwatches are not professional medical devices. Their data is just for daily reference. Shaky hands, loose watch bands and wrist tattoos will disturb the sensor and cause incorrect readings.

但智能手表并非专业医疗设备，监测数据仅作日常参考。手部晃动、表带松动、手腕纹身等情况，都会干扰传感器，导致心率数据不准确。

To get reliable data, you should wear your smartwatch snugly on your wrist. It should fit well but not feel too tight. In this way, the sensor can work stably and accurately.

想要获取精准可靠的数据，佩戴智能手表时需要贴合手腕，松紧适中、不紧绷。这样才能保证传感器稳定、精准地工作。

📝 重点核心词组（初中生必背）

1. tiny sensor 微型传感器 

2. blood vessel 血管 

3. pump blood 泵血、供血 

4. bounce back 反射、回弹 

5. light signal 光信号 

6. real-time heart rate 实时心率 

7. resting heart rate 静息心率 

8. for reference 仅供参考 

9. disturb the sensor 干扰传感器 

10. reliable data 可靠数据

📚 核心语法考点（初中高频）

1. instead of 介词短语用法：意为“代替、而不是”，后接名词/动名词，表取舍。 例句：It uses green light instead of other colors.

2. when 引导时间状语从句用法：主从句均用一般现在时，描述客观常识、常态现象。 例句：When your heart pumps blood, blood vessels expand.

3. 被动语态（get + 过去分词）用法：口语化被动表达，多用于科普场景，通俗易懂。 例句：Green light gets absorbed well by blood.

4. however 转折副词用法：表语义转折，单独成句，用逗号隔开，是阅读高频词。 例句：However, smartwatches are not professional medical devices.

5. to do 不定式表目的用法：置于句首/句末，表“为了……”。 例句：To get reliable data, you should wear the watch properly.

6. cause 动词用法用法：cause + 名词，表示“导致、引发某种结果”。 例句：Bad wearing habits cause incorrect readings.