1 (wiktionary) 2 (vi.wikipedia) 3 (en.wikipedia) 4 (glosbe)

Core Words Familarize yourself with the 'core words'.
Compounds Expand your vocabulary by studying more complex words built by the 'core words'.
Wordsense Learn about the wordsenses of the english term.

ETYMOLOGY

KOREAN 3.0 Eng Wordtype Etym. Gb Vie
☆☆ EFFECT; EFFICACY Noun 效果效果，功效，效力，成效，作用 hiệu quả
☆☆ BEING EFFECTIVE; BEING EFFECTUAL Noun 效果的有效的，有成效的，行之有效的 tính hiệu quả
☆☆ EFFECTIVE; EFFECTUAL Determiner 效果的有效的，有成效的，行之有效的 có tính hiệu quả