Question

After school, I looked for books about Mars. (I need help finding the Adjective Phrase please)

Answer 1

“About Mars” is the Adjective Phrase.

Adjective phrase describes “what kind of which ones”

So for example here

“After school, I looked for books about Mars.”

“About Mars” describes the kind of books so that makes it an Adjective phrase.

I hope this helps.

Answer 2

Your answer is “about Mars”