When we drill hi hi hi we call it Heaven 6.
Lo lo lo is earth.
It is then possible to name the rest of the drills after the trigrams
HLH - standard - would be Fire
LHL would be water
HLL would be Lake
etc
HHH - heaven
HHL - wind
HLL - lake
HLH - fire
LHH - thunder
LHL - water
LLH - mountain
LLL - earth
you will notice the deliberation of opposites:
fire and water is obvious
as is heaven and earth
wind, substance without sound vs thunder, sound without substance is more subtle