There are several irregular verbs in the Conditionnel whose stem changes and to which we would add the imparfait endings: ais, ais. ait. ions, iez, aient.

These are Avoir, Etre, Aller, Faire, Devoir, Pouvoir, Voir, Boire, Pleuvoir,  Falloir, Savoir, Venir , Vouloir, Recevoir. There new Tsems are as follows (in the same order)   AUR_ ,  Ser_, Fer_, Devr_, Pourr_ , Verr_ , Buvr_  , Pleuvr_ , Faudr_ , Viendr_   , Voudr_ , Recevr_

To each you would add the new endings depending on the subject.

Once you do they change the meaning of the sentence to would , except POURR_ , means could and Devr_  means should.

Je devrais manger _ I should eat.

Elle pourrait manger- She could eat.

Elle mangerait _ she would eat.