"什么...都/也" (shénme...dōu/yě) is a pattern often used to express "all" or "everything". This pattern also works with other question words, such as 哪儿 and 什么时候 in Chinese grammar.
Structures
The structure is very clear, as many Chinese grammar points are.
什么+noun.+都
什么+noun.+也
什么+都/也
Examples
Wǒ shén me dōu zhī dào.
我 什么 都 知道。
我 什么 都 知道。
I knew everything.
Negative Structures
The negative structure simply adds a 不 or a 没 after the 都/也.
什么+noun.+都/也+不
什么+noun.+都/也+没
Examples
Jīn tiān wǒ shén me dōnɡ xi dōu méi chī.
今天 我 什么 东西 都 没 吃。
今天 我 什么 东西 都 没 吃。
Today I didn't eat anything.
