a head of hair的用法和样例：
- A head of white-blond hair resembling tow.
- The boy has a head of soft, thick hair.
- With a good head of hair you don't need a hat.
- That boy has a head of woolly hair.
- It was so like smith’s work, so much more like the top of a strongly spiked wall than a head of hair.
- My brother has a bushy head of hair.
- not touch a hair of someone's head 不动某人一根毫毛,丝...