清晰

The photograph is not distinct.

The picture is in sharp focus.

The outlines of the distant hills are clearly discernible.

The radio has/gives good reception.

be clear and distinct

enunciate one's words clearly

sharp image (of sth)

have clarity of mind; have a lucid brain; have one's head screwed on the right way

be methodical; be well-arranged

have clearness/clarity of thinking; have an intellectual clarity

lucidity of thought

have a clear utterance/articulation

articulate distinctly/clearly; pronounce distinctly