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

Compounds Expand your vocabulary by studying more complex words built by the 'core words'.
Etymology Explore the origin of the 'core words'.
Wordsense Learn about the wordsenses of the english term.

TOPIK 11000 KOREAN WORDS

☆☆ COOPERATION; COLLABORATION; WORKING TOGETHER sự hiệp lực, sự hợp sức ☆ COOPERATIVE SPIRIT; TEAM SPIRIT; TEAMWORK tinh thần hiệp đồng, sự đồng tâm hiệp lực ☆ COOPERATION; COLLABORATION; COORDINATION sự cộng tác, sự phối hợp, sự hòa hợp ☆ COOPERATION; JOINING FORCES; COLLABORATION sự hiệp đồng, sự hợp tác
HSK 3.0 11000 CHINESE WORDS
7 协作  xiézuò cooperation, coordination

ENGLISH 6000 THEME WORDS

OXFORD 5000 CORE WORDS

TANAKA 6000 CORE WORDS