blender bulldozer 4

e to extrude plane, bisect near top surface

ctrl + r to loop cut the bisect line to increase segments,

select vertices on both sides, g to move

select top edge face, e to extrude

select extruded top corner edge, g to move

k to knife, c to cut through, select face, e to extrude

k to knife, c to cut thought, enable x-ray view

select faces, shift + d to duplicate, p to separate

select faces, x to delete 

create gap between compartments

enable x-ray view, select edges on separated compartment, g to move

reference:

knife tool:

https://www.google.com/search?q=blender+knife+cut+through&rlz=1C1FKPE_enCA959CA959&oq=blender+knife&aqs=chrome.1.69i57j35i39l2j0i512l7.4059j0j15&sourceid=chrome&ie=UTF-8#kpvalbx=_uxwjY_D5LLK80PEP0tSAuAM_28