Word: 密封 (mìfēng) 密封 dictionary entry mìfēng to seal up Full dictionary entry for 密封 Example sentences using 密封 2 sentences, showing page 1 of 1. 这些容器是密封的。 Zhèxiē róngqì shì mìfēng de. These containers are airtight. 饼干吃完以后，请把盒子密封好。 Bǐnggān chī wán yǐhòu, qǐng bǎ hézi mìfēng hǎo. After eating the cookies, please seal the box tightly.