translation.en: You're looking at the outside shell of the virus, and the yellow color here are those parts of the virus that are evolving very, very fast, and the blue parts are not evolving very fast.
translation.zh: 你们仔细看病毒的外壳 这些黄色的部分 进化得很快，非常快， 而那些蓝色的部分则进化得相对缓慢。