"Diligent study" means putting in consistent and focused effort to learn and understand something thoroughly.
Sentences with «diligent study»
Some people do prefer conformity over conviction, and they react to diligent study with studied disapproval. (rachelheldevans.com)
The pharm tech exam is not easy, and it will require diligent studying and preparation. (careertrend.com)
If you can't get it firmly entrenched into your head through diligent study, and then retrieved again, unassisted, under pressure... when need be... the «Yer out!» (remonline.com)