Nested three levels down:
When program statements are nested three levels down, as in this program, it is hard to see what is controlling what. To figure this out, match "brackets" as was done in a previous chapter.
The nesting is theoretically possible to any ideas of depth, although only a few levels are normally used in practical programs.
programming + nested 2 levels deep = About 983 results (0.62 seconds)
programming + nested 2 level down = About 71 results (0.62 seconds)
Deep is more common, it would seem. Down is also used.