to be clear (of a sight, sound, colour, etc.); to be bright; to be clear-headed; to be alert; to look upbeat; to be perky; to master (a skill)
clearness; clarity; skillfulness (skilfulness)
dark; dull; unsatisfactory; dissatisfying; unattractive; unappealing
clearly; brightly; crisply
cheerful (look); healthy (complexion)
cheerful (look); healthy (complexion)