Why not 'somos'? Being part of a school class, or any other class is a permanent state.
It is a location and that requires "estar"/"estamos". Estar: Position, Location, Action, Condition, Emotion(PLACE). Ser: Description, Occupation, Characteristic, Time, Origin, Relationship(DOCTOR). Oh I get what you mean such as, you graduated 20 years ago you are still in the same class(class of 1993). Not sure on that. Google translator gives "We are in the class of 1993" = "Estamos en la clase de 1993 ".
For anyone wanting to learn about DOCTOR & PLACE:
Her and I is grammatically poor English. Also why not say as a correct translation "We are the the same class."
That would not matter because nosotros is completely interchangable with ella y yo. In english her and i at the beginning of the sentance is not gramatically correct so it should not be the reaponse.
I believe that they have rectified the "her and I" issue, as you can see from the top of this thread where it says "she and I." Also, they are only interchangeable semantically, but, as far as translations go, Duolingo wants literal translations only. Therefore, no paraphrasing or semantic equivalents is ever accepted by Duolingo, for the most part.
Packedtogo, 'Ella' in Spanish translates to 'she,' not 'her.' The word for 'her' would be 'su' in Spanish. "She and I . . ." is perfectly acceptable English.
Remeber also that 'su' is possesive and can be used for both genders. "His book/ Her book" would both be 'su libro.'
«su» means "her" only as a possessive pronoun, as in "Her book was here." In "I gave her the book," "her" (indirect object pronoun) would be «le». In "I called her yesterday," "her" (direct object pronoun) would be «la». When there is a preposition involved right before the "her," it becomes «ella» again: "I gave the book to her." = «Le di el libro a ella.».
Let's remember to look at the date of posts we are responding to. The question was probably slightly altered since 2 years ago.
Her and I absolutely is poor English; She and I, however, is not.
We cannot put We as the subject because we lose information that was given to us in the original sentence. We is composed of She and I as opposed to He and I or even a group.
It is an incorrect option. "her" is the objective [and possessive] pronoun; it is not the subject pronoun. Since it is the subject in this sentence, it should be "she and I," not "her and I."