Tu est mon garçon - Why is 'est' wrong?

[AwesomeWelles]

I thought it was 'est', got told it's 'es' instead. I'm not sure I understand why....

[tonitheisen]

es is the tu form of the verb être.

[zebraman213]

être

je suis

tu es

il/elle est

nous sommes

vous êtes

ils/elles sont

[EnglishBob]

It's the same in English where it's "you ARE" and "he IS". In French it's "tu ES" and "il/elle EST".