Blackheads are what it's called when the comedo is open.

粉刺还是态时叫黑头。

When there's a comedo plus an infection that causes inflammation, that's a different kind of acne: pimples!

粉刺加上感染会引发炎，这就是另一种粉刺：面疱！

When the comedo closes, skin cells grow over the top of the plug and stop this oxidation from happening, so the whitish color of the sebum shows through.

当粉刺闭合，皮肤细胞将闭合口盖住，阻止了这种氧化，透过皮肤看到皮脂混合物就成了白色。