Home / HSK Vocabulary / HSK 7–9 / 密封 密封 mì fēng HSK 7–9 · C2 Meanings to seal up Quick facts HSK LevelHSK 7–9 CEFRC2 ← Back to HSK 7–9 word list Practice 密封 with flashcards MandoBridge uses spaced repetition to help you remember HSK 7–9 vocabulary — free on iOS and Android.