reason; logic

a reason / a motive

be damaged, be broken / be missing, to lack / be insufficient, be short / for the moon to wane

to act

action; behavior

to do

he / distal demonstrative, something far off removed from both speaker and listener: that / boyfriend

distal demonstrative, something far off removed from both speaker and listener: that, yon / particularly, male personal third person pronoun: he / by extension from he: boyfriend

he; boyfriend

logical / rational / reasonable / science