2 sentences

1. 那个家伙不怀好意。

   nà gè jiā​huo bù​huái​hǎo​yì.

   That guy is up to no good.

   Source: Dong Chinese Dictionary

2. 这个人贼眉鼠眼的，一看就不怀好意。

   zhè gè rén zéi​méi​shǔ​yǎn de, yī kàn jiù bù​huái​hǎo​yì.

   This guy looks shifty and up to no good.

   Source: Dong Chinese Dictionary