What exactly is the function of a participle and how can one be identified in a sentence?

A participle is a form of a verb that has a similar role to an adjective or adverb because it is used in sentences to modify a noun, noun phrase, verb or verb phrase.

Depending on the tense, one could indentify the participle in the sentence according to its ending: present participles of regular verbs end in - ing and past participles of regular verbs end in - ed.

Here are some examples:

This boring class makes me want to go home.

The healed child went back home.