What are "Aremos"?
Rashi: Sheaves of grain.
What is the significance of the matters mentioned?
Malbim: They are in decreasing order of severity. Pressing grapes is an Isur Skilah. We can say that they loaded piles before Shabbos, and transgressed [only] Shevisas Behemto 1 .
One must let his animal rest on Shabbos. This is mid'Oraisa, but there is no Misah or Kares for it. Buying and selling are forbidden mid'Rabanan. (PF)
What is the meaning of "va'A'id"?
Rashi: I testified against them not to do so. Ibn Ezra - it should say va'A'id Bam.
What is the meaning of "b'Yom Michram Tzayid"?
Rashi: On the day when they sell food and Tzayid, i.e. provisions - "va'Yiten Lahem Tzeidah la'Darech."
Malbim: They fixed Shabbos to be the market day. I warned them not to sell on that day.
