1)
How will the Mes' name be established on his inheritance?
1.
Rashi: Since his wife will come and go in his inheritance, people will say 'this was Machlon's wife'; his name will be mentioned on it.
2)
Why did he repeat "Edim Atem ha'Yom"? Verse 9 already said so!
1.
Malbim: Verse 9 refers to acquiring from Na'ami via money, a document or Chazakah. Our verse discusses Yibum, via which he acquires Eshes ha'Mes, and automatically Machlon's field.
