Meine Schwester und ich lesen abwechselnd vor.

and

Breakdown of Meine Schwester und ich lesen abwechselnd vor.

• ich: I
• meine: my
• die Schwester: the sister

Questions & Answers about Meine Schwester und ich lesen abwechselnd vor.

Why is it meine Schwester and not meiner Schwester?

Because meine Schwester is the subject of the sentence, so it is in the nominative case.

• meine Schwester = nominative feminine singular
• meiner Schwester is usually dative or genitive

Here, my sister and I are the people doing the action, so German uses the nominative: Meine Schwester und ich.

Why is it ich and not mich?

For the same reason: ich is nominative, and this sentence needs a subject pronoun.

• ich = I
• mich = me

In English, people often say me and my sister in casual speech, but in German the standard form here is meine Schwester und ich, because both parts are subjects.

Why is the verb lesen and not liest?