organize maven multi-module project in eclipse

Question

I have a huge Maven multi-module project. With similar structure

parentA
  - subA1
     - subA3
     - subA3
  - subA2

parentB
  - subB1
  - subB2

Answer 1

In Project Explorer, there's a down arrow, if you hover over it, it shows "View Menu".

Click on it, Project Presentation -> Hierarchical