Elucidate, Assiduous, Impregnable

Elucidate­- to make something clear; to explain something

Ex: The train conductor elucidated to the novice traveler that no, technically it was not off limits to eat pop rocks in the quiet car.

Assiduous- meticulous; showing attention to detail

Ex: The farmers longed for a more assiduous sign technician who wouldn’t be so careless as to let the lights go off on the “baby calf grazing area” sign so that all that remained illuminated was “baby gazing area”.

Impregnable- impenetrable; unable to be defeated

Ex: To a high-school dropout, the google campus seemed like an impregnable fortress, with no hope of entry. But, as her resume showcased, she had accrued two years of experience googling “quick, easy airfryer recipes to help you overcome your anorexia”, which surely had to count for something, so she figured she would at least throw her hat in the ring.