The colours are magnificent, but the question of exactly why some trees turn yellow or orange, and others red or purple, is something which has long puzzled scientists.

这些颜色很瑰丽，但究竟为什么有些树会变成黄色或橙色，而有些树会变成红色或紫色，这个问题一直困扰着科学家。

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Choose a light yellow or orange colour.

选择一种明亮的黄色或橙色。

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Everyone else knew a lot of the moves already and had yellow or orange belts.

那里每一个人都认识很多已经拥有蓝带或者橙带的学员。

youdao

Now the wool is orange or yellow.

VOA: special.2010.08.02

Board a green flag boat, ignoring those with orange, yellow or no flags, and try to get a seat on the right (starboard) side to avoid the glare of the afternoon sun.

BBC: Take the boat out of Bangkok

It has a pure yellow hue with no green or orange modifying color and the color distribution is very even with no visible zoning present, according to a joint statement from USMS and Bid4Assets.

FORBES: Feds to Sell Seized 43-Carat Fancy Yellow Diamond

Today the United States Government raised the national threat level from an Elevated to High risk of terrorist attack - or from Code Yellow to Code Orange.

BBC: NEWS | Americas | US terror alert: Full text