> it’s countable it follows normal rules, if it’s not, it goes back to singular form. You'd have a hard time counting all the stars, but "sky of star" doesn't

> it’s countable it follows normal rules, if it’s not, it goes back to singular form. You'd have a hard time counting all the stars, but "sky of star" doesn't work like "head of hair" does. I love how expressive English is, but it's got issues for sure.