HSK 7-9
敞开
chǎngkāi动副
to open wide; unrestrictedly
教室门窗全部敞开通风。
Jiào shì mén chuāng quán bù chǎng kāi tōng fēng.
All classroom doors and windows are open wide for ventilation.
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Appears across levels (7-9) in the HSK 3.0 word list.