黑头发英语是black hair，白头发居然不是white hair？

例句：

①Gray hair is a mark of age.

灰白头发是老年人的特征。

②Mother: Susie, every time you misbehave, I will get another gray hair.

母亲: 苏茜, 每次你表现不好, 我就会多长一根白头发。

◉例句：

①My hair is going gray/went gray.

我长白头发了。

②My father's hair is going gray.  

我父亲的头发渐渐变成灰白。

◉例句：

①I'd like to dye my hair.

我想要染发。

② Do you think I could get away with dyeing it purple?

你认为我把它染成紫色好看吗？

◉例句：

①Ideally coloring is done after a perm.
理想的染发应该在烫发之后进行。

②Would you like a permanent or just a setting?

你是要烫发还是只是做一下？

◉例句：

①I have a hair transplant.

我去植了发。

②The patient had received a heart transplant.

该病人接受了心脏移植。