R如何列出清单?

I don't know how to make list of lists in R. I have several lists, I want to store them in one data structure to make accessing them easier. However, it looks like you cannot use a list of lists in R, so if I get list l1 from another list, say, l2 then I cannot access elements l1. How can I implement it?I don't know how to make list of lists in R. I