5 sentences

1. 这一带的养殖业以淡水鱼为主。

   zhè yī​dài de yǎng​zhí​yè yǐ dàn​shuǐ yú wéi​zhǔ.

   The aquaculture industry in this area is dominated by freshwater fish.

   Source: Dong Chinese Dictionary

2. 美国的中西部地区以农业为主。

   Měi​guó de zhōng​xī​bù dì​qū yǐ nóng​yè wéi​zhǔ.

   The Midwestern United States is primarily agricultural.

   Source: Dong Chinese Dictionary

3. 该地区的出口商品以农产品为主。

   gāi dì​qū de chū​kǒu shāng​pǐn yǐ nóng​chǎn​pǐn wéi​zhǔ.

   The region's exports consist mainly of agricultural products.

   Source: Dong Chinese Dictionary

4. 该地区的植被以亚热带常绿阔叶林为主。

   gāi dì​qū de zhí​bèi yǐ yà rè​dài cháng​lǜ kuò​yè​lín wéi​zhǔ.

   The vegetation in this region is dominated by subtropical evergreen broad-leaved forests.

   Source: Dong Chinese Dictionary

5. 医疗卫生工作应当以预防为主。

   yī​liáo wèi​shēng gōng​zuò yīng​dāng yǐ yù​fáng wéi​zhǔ.

   Medical and health work should focus primarily on prevention.

   Source: Dong Chinese Dictionary