Easy. A friend of mine started a small business. He had an intern/trainee and one day, one technician who was tasked to teach the trainee told my friend: "He will never learn. He eats grass". The meaning is he's a sheep/animal/stupid.
So if a human eats grass, I can easily imagine a horse not eating bread.
It's a masculine noun, which would normally be N, unless the word ends in й or ь. The plural ending then becomes и.
Лошадь is a feminine noun.
Masculine and feminine nouns can end in -ь. In the nominative plural, words which end in -ь change to -и, regardless of their gender.
Masculine words with a consonant ending most commonly end in -ы, not -и. Uncommonly, consonant ending words can end in -а or -я. So:
- -consonant ending adds: ы, а, я (or и if the ending consonant is ж, г, к, х, ч, ш, щ)
- -ь changes to: и
Its not (just) the speed making things difficult for the audio aspect, but also the intonation seems a little off. (In fact the last two words almost sounded like something in English played backwards.) It rises and falls in what feels like an unusual way that i dont think would be the case with a human speaker.
Basically, you/we probably need to supplement duo with recordings of live speakers to get a better ear for pronunciation.
Есть is the infinitive "to eat," which has a 3rd person plural present tense conjugation едят (ie. They eat/are eating. Keep in mind that есть is also the irregular present tense conjugation of быть for all persons and numbers. You are most likely (and on Duolingo, exclusively) going to see it in the context of "there is/are" or in the construction у + [person in genitive], meaning someone "has" something. Пьёшь is the 2nd person singular present tense conjugation of пить, to drink.