prism

to use / to employ / to make use of, to apply / to spend

(mathematics, chemistry) analysis

to analyze

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

a light, beam, illumination / a gleam, glow, ray / a glimmer, shine, sparkle / a luster/lustre, polish, sheen / glory, influence, power / a glimmer, gleam / positive aspect

use one thing for many purposes / work someone hard

to use one's head