Why is you also plural?

Answer 1

'There is a concept in English and many other languages called "grammatical person", which describes the relationship of the speaker to the event.

The conjugation of a verb depends on both the grammatical person and singular/plural.

First person: I (singular) am a teacher. We (plural) are teachers.

Second person: You (singular) are a teacher. You (plural) are teachers.

Third person: He (singular) is a teacher. They (plural) are teachers.'

Answer 2

The use of "you" as both singular and plural is a feature of the English language that evolved over time. In many languages, such as Italian or French, there are distinct words for addressing one person (singular) versus multiple people (plural). English, however, only has "you" for both singular and plural, which can sometimes lead to confusion.