Learn Spanish (Latin America): Nos asombra que ellos vivan en el bosque. - It amazes us that they live in the forest.

The main verb, asombrar (to amaze), expresses an emotion. When you express an emotional reaction to what someone else does using que, the second verb must be in the subjunctive. Since the people being amazed (nos) are different from the people living in the forest (ellos), we use the subjunctive vivan.

Why does the sentence start with nos asombra instead of a word for 'we'?

The verb asombrar works just like gustar. Instead of saying 'We are amazed,' the Spanish structure is closer to 'It amazes us.' The pronoun nos means 'to us,' and the entire second half of the sentence (que ellos vivan en el bosque) acts as the subject doing the amazing.

Could I leave out ellos and just say que vivan en el bosque?

Yes, you can! Spanish often drops subject pronouns. However, because vivan could technically refer to ellos, ellas, or ustedes (you all), keeping ellos in the sentence prevents any confusion about who exactly is living in the forest.

How do we get the form vivan from the verb vivir?