In China, we use red paper for hongbao because red means good luck.

在中国，我们用红色的纸做红包，因为红色寓意着好运。

youdao

In Russia, red means beautiful.

在俄罗斯，红色意味着美丽。

youdao

Green means more meat, red means stop.

绿色表示接着上肉，红的表示吃够了。

youdao

A red light means get into position. Yellow light means ready.

VOA: standard.2009.09.10

In the very red means in that part of the brain is stimulated by the centre of your visual field.

红色部分说明这部分的大脑,收到视野中心的刺激。

斯坦福公开课 - 7个颠覆你思想的演讲课程节选

If we think that our knowledge is positive, we say "red" in a red light means stop.

如果我们主动认知，红灯的意思是停。

耶鲁公开课 - 文学理论导论课程节选

Red means a little bit warmer than average, blue means cooler than average, and white is average.

CNN: Better 'baby picture' of universe emerges

In case you don't have your smartphone app handy, the taps are equipped with LED lights to show the water's filter status as well -- blue means clean, yellow means not so much and red means you should probably get a new filter, pronto.

ENGADGET

Red tape means that firms who play host to minors face legal and insurance problems.

ECONOMIST: Education