Intelligent = intellectual abilities as a direct result of education or favourable cultural impact; someone who is capable of deeply analysing complex situations.
intelligent thinking
intelligent teacher
an intelligent scholar capable of interpreting ancient authors, etc.
Clever = natural intelligence which one is born with; practical, pragmatic qualities of a person.
He was clever though he did not have proper education.
She was clever; she knew how to use her money.
Smart (quick-witted) = natural intelligence + the ability to understand the situation:
He is pretty smart and will get his promotion.
Clever, silly, friendly, unfriendly, kind, unkind, mean, generous, greedy, lazy, hard-working, shy, extrovert, talkative, quit, calm, smart, intelligent, energetic, ambitious, chatty, tolerant, cheerful, easy-going, open, organized, reserved, sensitive, unreliable, adventurous, stupid, messy, brave, serious, outgoing, tolerant, cowardly, frank, selfish, lively, sensible, polite, rude, thoughtful.
