2 sentences for 死气沉沉 (sǐ​qì​chén​chén)

1. 这里的气氛死气沉沉的，让人感到很压抑。

   zhè​lǐ de qì​fēn sǐ​qì​chén​chén de, ràng rén gǎn​dào hěn yā​yì.

   The atmosphere here is lifeless and makes people feel depressed.

   Source: Dong Chinese Dictionary

2. 他最近总是死气沉沉的，好像对什么都不感兴趣。

   tā zuì​jìn zǒng​shì sǐ​qì​chén​chén de, hǎo​xiàng duì shén​me dōu bù gǎn xìng​qù.

   He has been very listless lately, as if he's not interested in anything.

   Source: Dong Chinese Dictionary