WeChat limits the amount that can be sent in a single red packet to 200 yuan ($29).

微信将单个红包的金额限制在200元（29美元）。

youdao

He sent her a single red rose.

他送给她一支红玫瑰。

《牛津词典》

A single red LED shows that the power is switched on.

单支红色发光二极管表示电源已接通。

《牛津词典》

When the Atari 2600 was introduced, it came with a joystick equipped with a single red button.

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The VIO, installed on a user's desktop, displayed only a single red dot.

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Crossing Bloomsbury Street, just by the British Museum, it can often take southbound traffic up to ten minutes to get through a single red light.

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