这款新的MK系列耳机音质非常出色。

The new ___MK series headphones have excellent sound quality.

我最喜欢的游戏角色来自真人快打系列。

My favorite game character is from the ___MK series.

我妈妈最近开始使用MK的产品。

My mom recently started using ___MK products.

太阳核心的温度约为15兆开尔文。

The temperature at the Sun's core is about 15 ___MK.