HSK 5
一旦
yídàn副
in case (sth happens); if; once (sth happens, then...); when
一旦发现问题就马上报告。
Yí dàn fā xiàn wèn tí jiù mǎ shàng bào gào.
Report the problem as soon as it is discovered.
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Hold the button, say it, then let go.
Other HSK words sharing a character
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New in the HSK 3.0 word list at level 5.