Then the Lord said to Moses, "Go in to Pharaoh and tell him: This is what the Lord says: Let My people go, so that they may worship Me.
References for Exodus 8:1
But if you refuse to let them go, then I will plague all your territory with frogs.
The Nile will swarm with frogs; they will come up and go into your palace, into your bedroom and on your bed, into the houses of your officials and your people, and into your ovens and kneading bowls.
The frogs will come up on you, your people, and all your officials."
The Lord then said to Moses, "Tell Aaron: Stretch out your hand with your staff over the rivers, canals, and ponds, and cause the frogs to come up onto the land of Egypt."
References for Exodus 8:5
When Aaron stretched out his hand over the waters of Egypt, the frogs came up and covered the land of Egypt.