3 sentences

1. 别听他们瞎说。

   bié tīng tā​men xiā​shuō.

   Don't listen to their nonsense.

   Source: OpenSubtitles

2. 没有经过实地调查，你不能在这里瞎说。

   méi​yǒu jīng​guò shí​dì diào​chá, nǐ bù néng zài zhè​lǐ xiā​shuō.

   You shouldn't make unfounded claims without an on-site investigation.

   Source: Dong Chinese Dictionary

3. 他病得不轻，一直在说胡话，净瞎说。

   tā bìng de bù qīng, yī​zhí zài shuō​hú​huà, jìng xiā​shuō.

   He is quite ill and has been talking deliriously, nothing but nonsense.

   Source: Dong Chinese Dictionary