וַיֵּ֤ט אַהֲרֹן֙ אֶת־יָד֔וֹ עַ֖ל מֵימֵ֣י מִצְרָ֑יִם וַתַּ֙עַל֙ הַצְּפַרְדֵּ֔עַ וַתְּכַ֖ס אֶת־אֶ֥רֶץ מִצְרָֽיִם׃
And Aaron stretched out his hand over the waters of Egypt; and the frogs came up, and covered the land of Egypt.
Read halakhic rulings (Jewish law) on Exodus 8:2: and classical halakhic sources.