Bonjour Madame !
I have carefully read the green box which states that when y pronoun comes after ER verbs in tu form in L’Impératif , then the dropped-out s is recovered.
But for the verbs like ouvrir, couvrir , offrir , découvrir which though are “IR” verbs but are conjugated like “ER” verbs , will this case persist for them also ?
If so please provide a few examples to illustrate the same.
Bonne journée !