Why did Moshe say "Lechem Lisbo'a", but "Basar Le'echol"?
Rashi and Seforno: The Torah is teaching us Derech Eretz - that it is in order to eat one's bread (which constitutes one's staple diet) to satisfaction, but not one's meat, which is a luxury. 1
To break with the way of the Egyptians, who cared only about self-indulgence (Seforno).
Why did Moshe add "bi''Shemo'a Hashem es Telunoseichem", which is obvious?
Seforno: Moshe explained that part of his Tefilah was that Hashem should send food in such a way that Yisrael should realize that their complaints were against Him (and not against Moshe and Aharon), and that He had now answered them.