Breakdown of Die Nachbarn unterstützen einander.
der Nachbar
the neighbor (male)
der
who, which, that (relative pronoun; die, das)
unterstützen
to support
einander
each other
Questions & Answers about Die Nachbarn unterstützen einander.
Could I say Die Nachbarn unterstützen sich instead?
Yes, you can! In the plural, the reflexive pronoun sich can also mean 'each other'. However, sich can sometimes be ambiguous. Without context, Die Nachbarn unterstützen sich could technically mean 'The neighbors support themselves.' Using einander makes it 100% clear that they are supporting each other, not themselves.
Does einander change its ending depending on the grammatical case?
No, it is completely invariable when used on its own. The verb unterstützen requires an accusative direct object, so einander is in the accusative case here. If you used a verb that requires the dative case (like helfen), it would still just be einander (Sie helfen einander).
Where does the word einander come from?
It is simply a combination of the words ein (one) and ander (other). It translates perfectly to the English phrase 'one another'.
Why isn't there a preposition attached to einander here, like in miteinander?