To whom does "Goyim" refer?
Rashi: Pharaoh Melech Mitzrayim.
What is the meaning of "va'Yishme'u Elav Goyim"?
Radak: Pharaoh, who was in Eretz Chamas, heard that [Yeho'achaz] invaded Egypt 1 , and they seized him when he returned from there.
Malbim: Pharaoh came against him.
Either he explains "va'Yishme'u" to mean 'they paid attention to', or he explains "Elav" like Alav (they heard about him). (PF)
What is the meaning of "b'Shachtam Nispas"?
Rashi: They dig holes and cover them with straw, and the Chayah falls inside. Radak ? this is like "Koreh Shachas" (Mishlei 26:27).
Radak citing Targum Yonasan: He was caught in his fortress.
What are "Chachim"?
Rashi: They are like iron rings. They pierce his nose (the wall between the nostrils), and pull him via the rings.
Radak, Targum Yonasan: They are iron chains.
