3 sentences

1. 他通过做兼职来赚取额外的收入。

   tā tōng​guò zuò jiān​zhí lái zhuàn​qǔ é​wài de shōu​rù.

   He earns extra income by doing part-time jobs.

   Source: Dong Chinese Dictionary

2. 他利用周末时间去做家教赚取学费。

   tā lì​yòng zhōu​mò shí​jiān qù zuò jiā​jiào zhuàn​qǔ xué​fèi.

   He uses his weekends to work as a tutor to earn money for his tuition.

   Source: Dong Chinese Dictionary

3. 这家公司通过出口贸易赚取了大量利润。

   zhè jiā gōng​sī tōng​guò chū​kǒu mào​yì zhuàn​qǔ le dà​liàng lì​rùn.

   The company earned large profits through export trade.

   Source: Dong Chinese Dictionary