树叶变成黄色用英语叫做 "the leaves turn yellow"。
来源：这是一个与自然界相关的表达方式，树叶变黄是指树叶由绿色变成黄色的过程，这是自然界中常见的现象。
例句：
The leaves of the tree turned yellow in the fall.
(秋天树叶变黄了。)
As the temperature dropped, the leaves on the bushes turned yellow and fell off.
(随着气温的下降，灌木丛上的叶子变黄并掉落。)
The leaves of the maple tree turned yellow and red in the autumn.
(枫树的叶子在秋天变成了黄色和红色。)