adj.白发苍苍的；老的
A band of gray hair encircled his bald dome. 他的秃头顶四周长着一圈灰白的头发。
He ran his hand through his thinning gray hair. 他用力捋他那愈见稀疏的灰头发。
Why does the first gray hair stick straight out? 为什么最初的白头发会挺得笔直的（那么显眼）?
I do not realize she has so much gray hair now. 我没注意到她现在有那么多白头发。
A wisp of gray hair sticks out from under her hat. 一绺灰白头发从她的帽子下露了出来。
