That's because a person is not operating the water in that statement. In this case, we have a person who was directly accused of typing "angrily." If "Poseidon

That's because a person is not operating the water in that statement. In this case, we have a person who was directly accused of typing "angrily." If "Poseidon angrily pounded the shore with waves," you'd think yes, he's pissed about something.