"谁也/都" (shéi yě/dōu) is a pattern used to express "everyone" in Chinese. The placement of the question word 谁 is very similar to the way 什么 can be used to express "every", along with other question words like 哪儿 and 多少 in Chinese grammar.

Examples

Shuí dōu huì xué xí hàn yǔ.
谁 都 会 学习 汉语。
Everyone can study Chinese.