6 sentences

1. 讲到工作，他从不马虎。

   jiǎng dào gōng​zuò, tā cóng bù mǎ​hu.

   When it comes to work, he is never careless.

   Source: Dong Chinese Dictionary

2. 凡事须得致意，不可马虎。

   fán shì xū děi zhì​yì, bù kě mǎ​hu.

   One must be attentive to everything and not be careless.

   Source: Dong Chinese Dictionary

3. 做事要认真，不能马虎糊弄。

   zuò​shì yào rèn​zhēn, bù néng mǎ​hu hù​nong.

   Work must be done conscientiously; you shouldn't just muddle through it.

   Source: Dong Chinese Dictionary

4. 我们要抓紧生产安全，不能有丝毫马虎。

   wǒ​men yào zhuā​jǐn shēng​chǎn ān​quán, bù néng yǒu sī​háo mǎ​hu.

   We must focus on production safety and cannot afford to be careless.

   Source: Dong Chinese Dictionary

5. 他办事一向很马虎，所以大家都不太信任他。

   tā bàn​shì yī​xiàng hěn mǎ​hu, suǒ​yǐ dà​jiā dōu bù tài xìn​rèn tā.

   He is always careless in his work, so everyone lacks trust in him.

   Source: Dong Chinese Dictionary

6. 那位老教授对待学术事必躬亲，从不马虎应付。

   nà​wèi lǎo jiào​shòu duì​dài xué​shù shì​bì​gōng​qīn, cóng bù mǎ​hu yìng​fu.

   The old professor takes a hands-on approach to his academic work and is never sloppy or perfunctory.

   Source: Dong Chinese Dictionary