1
a stoplight comes on when + clause
此处 stoplight 指刹车灯，come on 表示“亮起”；美式英语中它也可指红绿灯。
A stoplight comes on when you press the brake pedal.
踩下刹车踏板时，刹车灯会亮起。
刹车灯；制动灯
先理解核心含义，再看它在真实句子里的用法。
刹车灯；制动灯
a red light on the back of a vehicle that comes on when the brakes are applied
A stoplight comes on when you press the brake pedal.
踩下刹车踏板时，刹车灯会亮起。
车辆后部在刹车时亮起的灯,即刹车灯。
A light on the rear of a vehicle that is activated when braking; a brake light.
When I pressed the brake pedal, the stoplight at the back of the car came on.
当我踩下刹车踏板时，汽车尾部的刹车灯亮了。
The driver behind me noticed my stoplight and slowed down in time.
我后面的司机看到我的刹车灯，及时放慢了速度。
You should check your stoplights regularly to make sure they work.
你应该定期检查刹车灯，确保它们能正常工作。
此处 stoplight 指刹车灯，come on 表示“亮起”；美式英语中它也可指红绿灯。
A stoplight comes on when you press the brake pedal.
踩下刹车踏板时，刹车灯会亮起。
汽车通常有左右两个刹车灯，所以常用复数 stoplights；be out 指灯不亮。
One of my stoplights is out, so drivers behind me can't tell when I'm braking.
我的一个刹车灯不亮了，后面的司机看不出我什么时候在刹车。
signal 作动词“显示、表明”，后接 that 从句。
A stoplight signals that the car is slowing down.
刹车灯表示汽车正在减速。
Not this
The stoplight is red, so we must stop.
Use this
The traffic light is red, so we must stop.
在这里 stoplight 是‘刹车灯’，不是‘交通信号灯’；表示路口的红绿灯时应用 traffic light。
Not this
The car has two stoplight at the rear.
Use this
The car has two stoplights at the rear.
stoplight 是可数名词，two 后须用复数形式；汉语名词无单复数变化，因此容易漏加 -s。
Not this
I saw stoplight on the car behind.
Use this
I saw a stoplight on the car behind.
stoplight 是可数名词单数，前面需要不定冠词 a；汉语没有冠词系统，所以学习者常会遗漏。
Focus on the distinctions below. Other candidates are kept compact until a reliable usage note is available.
尾部刹车灯
The car's rear stoplight is dim, so drivers behind may not see it clearly.
这辆车的尾部刹车灯很暗，后面的司机可能看不清。
刹车灯开关
A faulty stoplight switch can keep the brake lights on even when you're not braking.
刹车灯开关故障会使刹车灯在你没有刹车时也一直亮着。
刹车灯灯泡
Replacing a stoplight bulb usually takes only a few minutes.
更换刹车灯灯泡通常只需几分钟。
烧坏的刹车灯
You should replace a burned-out stoplight promptly.
应尽快更换烧坏的刹车灯。
刹车灯一直亮着
If the stoplight stays on, the brake pedal switch may be misaligned.
如果刹车灯一直亮着，可能是刹车踏板开关没有对准。
Use stoplight naturally, then get feedback on meaning, tone, grammar, and phrasing.
Revisit a common error or keep this word in your review list.
记忆联想：stop（停）+ light（灯）＝红绿灯；红灯一亮就要停。
语域：neutral 常见场景：driving、car repair、vehicle safety inspection 该词指汽车刹车灯（制动灯）时属于中性日常表达，通常用于驾驶、车辆维修和车辆安全检测等场景；在正式文件或维修手册中，更常见的是 brake light。
以上六个词都以 -light 结尾，发音为 /laɪt/，与 stoplight 押韵；重音在第一个音节。注意：lightning /ˈlaɪtnɪŋ/ 看起来像，但不是押韵；lighter /ˈlaɪtə/ 末尾多了元音，也不押韵。
Dictionary facts from ECDICT, WIKTIONARY.