Final answer:
In the sentence provided, the three verbs are 'held,' 'asked,' and 'left,' each indicating a different action performed by the subjects within the sentence.
Step-by-step explanation:
The three verbs in the sentence "My mom held up the empty milk carton and asked, 'Who left this in the fridge?'" are held, asked, and left. The verb held indicates what the mom did with the milk carton, asked shows the action of inquiring, and left refers to the action of someone placing the milk carton in the fridge previously. Identifying verbs is crucial for understanding the actions taking place in a sentence.