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

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Compounds Expand your vocabulary by studying more complex words built by the 'core words'.
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ETYMOLOGY

HAN VIET: tín phong 信封

KOREAN 3.0	Eng	Wordtype	Etym.	Gb	Vie
☆☆☆	ENVELOPE	Noun	封套	信封	phong bì