like: sự lạc quan
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Composite Words Listening Comprehension Oxford Topics Duolingo Topics 315 Activities
BEGINNER LEVEL
exact:
VNEN 
sự lạc quan * ☊ 
optimism * ☊
[ sự ] : deed, act, action event, occurrence, (classifier for actions, states)
[ lạc ] : peanuts; to be lost, go astray, lose one’s way
[ quan ] : (1) official, officer; (2) franc (unit of currency); (3) coffin; (4) sense