What is the meaning of "Az Tir'i v'Nahart"?
Rashi citing Targum Yonasan: You will see and [Radak - your face will] be bright. Radak - The root of Tir'i is Ra'ah. Many (e.g. Ibn Ezra) erred, and put a Gaya 1 under the Tov, i.e. the root is Yarei (fear). V'Nahart is like "v'Al Tofa Alav Naharah" (Iyov 3:4), "Hibitu Elav v'Naharu" (Tehilim 34:6).
Malbim: He will be like one who sees something that never crossed his mind. He does not believe himself if he truly saw it - perhaps he imagined it - until v'Nahart, he looks carefully and sees that he truly saw it.
This is a minor accent, two syllables before the true accent. They hold that there is a Shva Na under the Reish, so it is considered a syllable. (PF)
What will you see?
Radak: You will see your children coming from every side.
What is "u'Fachad"?
Rashi: You will be astounded. Radak - this is like a person who is startled by great good that comes suddenly.
Why does it say that your heart will widen?
What is the meaning of "Yehafech Alayich Hamon Yam"?
Rashi citing Targum Yonasan: Will transfer to you wealth of the west.
Radak: You were destroyed and desolate. Now you will be the opposite; many nations will come to you like the multitude of the sea.
Malbim: It is as if the multitude of the sea was reversed on you - all seafarers will turn to come to you.
What is "Cheil Goyim"?
Rashi citing Targum Yonasan: The property of star-worshippers.