1. Onto indicates movement from one position to another one.       

Pattern 1: verb + onto + noun
The child hopped onto the bed.

Typical verbs used before onto:
drip, fall, hop, jump, move, run, spill, step                 

Pattern 2: verb + noun + onto + noun
We moved all the books onto the desk.           

Typical verbs used with this pattern:
drip, drop, move, spill, transfer                       

2. Onto indicates knowledge of misbehavior.                       

Pattern: be + onto + noun.
The police are onto that gang about the missing money.         

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