I found this example:
Nǐ ná zheyòng ba, shénme shíhòu huán dōu kěyǐ.
You can have it as long as you want.
I am confused about the grammar structure behind 什么时候还都可以 (literally: any time you return it is ok). How is it possible 都 occurs after the verb 还 (to return)? Until now, I always saw 都 before any verb.