为什么头发会变白？

作者：张恒选

来源：中学生英语, 2020, (25): 32-33.

<正>If you’ve ever seen a picture of a grandparent when they are young and wondered what made their hair go from dark to light, join us as we find out why hair goes gray.如果你曾经看过爷爷奶奶年轻时的照片,想知道是什么让他们的头发颜色由深变浅,那就加入我们吧,我们一起找出头发变白的原因。