The subject of the sentence is who or what the sentence is about. The subject is "bird". The verb is an action or a linking verb that connects the subject with its description. In this sentence the verb "fed" is an action verb. To identify the direct object, you must ask subject-verb-what? The bird fed what? She fed worms. Worms is the direct object. Sometimes it's also good to think about what was touched or interacted with first. First the bird got the worms, then brought them to her young. Young is not an adjective in this sentence, it is a noun that means children. Young an indirect object because it receives the worms. It is the second step for the sentence to be acted out.
