2 sentences

1. 他太冒失了，还没听完要求就动手做了。

   tā tài mào​shi le, hái méi tīng wán yāo​qiú jiù dòng​shǒu zuò le.

   He was too impulsive; he started working before he'd even finished hearing the requirements.

   Source: Dong Chinese Dictionary

2. 他冒失地问起对方的私人收入，让人感到很不快。

   tā mào​shi de wèn​qǐ duì​fāng de sī​rén shōu​rù, ràng rén gǎn​dào hěn bù​kuài.

   He rashly asked about the other person's private income, which made them feel very uncomfortable.

   Source: Dong Chinese Dictionary