essayer and nettoyer

Verbs ending in -ayer (like "essayer") have two possibble conjugations with je, tu, il/elle/on and elles/ils. So, you can, interchangeably, use the "i" version (essaie/s), or the "y" version (essaye/s).

That difference is meant to accommodate pronunciation which can be different in various French speaking areas: [ ε ] ou [ εj ] ("essè" ou "esseille").

So you can use:

"J'essaie" or "j'essaye" - "tu essaies" ou "tu essayes" - "il/elle/on essaie" or "il/elle/on essaye" - "ils/elles essaient" or "ils/elles essayent"

However, with "nous" and "vous", you should use "y" because the sound [ j ] is maintained:

nous essayons [ εjõ ] vous essayez [ εjé ]

For verbs in -oyer ("nettoyer"= to clean), you have no choice, the "i" version prevails. Je nettoie, tu nettoies, il/elle/on nettoie [ netwa ]
Written by Sitesurf@https://www.duolingo.com/comment/242649