5 sentences

1. 水都是在封闭的系统里循环的。

   shuǐ dōu shì zài fēng​bì de xì​tǒng lǐ xún​huán de.

   Water circulates in a closed system.

   Source: OpenSubtitles

2. 桥封闭了。

   qiáo fēng​bì le.

   The bridge is closed.

   Source: OpenSubtitles

3. 由于大雪，通往山区的道路已经封闭了。

   yóu​yú Dà​xuě, tōng​wǎng shān​qū de dào​lù yǐ​jīng fēng​bì le.

   Due to heavy snow, the roads leading to the mountains have been closed.

   Source: Dong Chinese Dictionary

4. 这个偏僻的村庄处于一种相对封闭的状态。

   zhè gè piān​pì de cūn​zhuāng chǔ​yú yī zhǒng xiāng​duì fēng​bì de zhuàng​tài.

   This remote village is in a state of relative isolation.

   Source: Dong Chinese Dictionary

5. 那家无证经营的工厂已被有关部门依法封闭。

   nà jiā wú zhèng jīng​yíng de gōng​chǎng yǐ bèi yǒu​guān bù​mén yī​fǎ fēng​bì.

   The unlicensed factory has been shut down by the authorities according to the law.

   Source: Dong Chinese Dictionary