3 sentences

1. 由于城市改建，这几家工厂已经搬迁了。

   yóu​yú chéng​shì gǎi​jiàn, zhè jǐ jiā gōng​chǎng yǐ​jīng bān​qiān le.

   Due to urban redevelopment, these factories have been relocated.

   Source: Dong Chinese Dictionary

2. 体育场经过改建后，观众席位增加了一倍。

   tǐ​yù​chǎng jīng​guò gǎi​jiàn hòu, guān​zhòng xí​wèi zēng​jiā le yī bèi.

   After the stadium was renovated, its seating capacity doubled.

   Source: Dong Chinese Dictionary

3. 旧工厂被改建成了现代化的创意园区。

   jiù gōng​chǎng bèi gǎi​jiàn chéng le xiàn​dài​huà de chuàng​yì yuán​qū.

   The old factory was converted into a modern creative park.

   Source: Dong Chinese Dictionary