HSK 3
Bié zài bèihòu tōujī-mōgǒu, zhèngdà-guāngmíng de zuòshì.
Don't sneak around behind people's backs. Do things openly and honorably.
HSK 4
Tā yǐjīng gǎiguò-zìxīn, bù zài tōujī-mōgǒu le.
He's turned over a new leaf and given up his shady ways.
HSK 6
Nà bāng xiǎohùnhun zhěngtiān tōujī-mōgǒu.
That gang of hoodlums is always up to petty thievery.