sima felület – smooth surface
sima ügy >figurative sense: smooth sailing

gyenge ember – weak man
gyenge egészség – poor health

könnyű / nehéz bőrönd – light / heavy suitcase
könnyű / nehéz feladat – easy / difficult task

alap = basis, base, foundation > this word is a noun, but can be used as adjective and then it is written together with the word it modifies.

alapműveltség – basic education
alapelv – fundamental principles