2 The construction here uses the deictic particle and the participle to convey the imminent future: “I am going to plague/about to plague.” The verb נָגַף (nagaf) means “to strike, to smite,” and its related noun means “a blow, a plague, pestilence” or the like. For Yahweh to say “I am about to plague you” could just as easily mean “I am about to strike you.” That is why these “plagues” can be described as “blows” received from God.
3 Heb “plague all your border with frogs.” The expression “all your border” is figurative for all the territory of Egypt and the people and things that are within the borders (also used in Exod 10:4, 14, 19; 13:7). This word for frogs is mentioned in the OT only in conjunction with this plague (here and Pss 78:45, 105:30). R. A. Cole (Exodus [], ) suggests that this word “frogs” (צְפַרְדְּעִים, tséfardé’im) may be an onomatopoeic word, something like “croakers”; it is of Egyptian origin and could be a Hebrew attempt to write the Arabic dofda.

In other versions

But if you refuse to let them go, behold, I will plague all your country with frogs.

If you refuse to let them go, I will send a plague of frogs on your whole country.

But if you refuse to let them go, then I will plague all your territory with frogs.

If you refuse to let them go, I will send a plague of frogs across your entire land.

And if you are refusing to release, look, I am going to plague all of your territory with frogs.

And if thou refuse to let them go, behold, I will smite all thy borders with frogs:

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