hair可数还是不可数

例句：

She walked forward and embraced him and stroked his tousled white hair.

她走上前拥抱他并轻抚他凌乱的白发。

Applying the dye can be messy, particularly on long hair.

涂抹染发剂可能会搞得一团糟，特别是长发。

His long, uncovered hair flew back in the wind.

他那露在外面的长发随风向后飞舞。