<u>Verbals</u> are verbs which function as nouns or adjectives. Gerunds (-<em>ing </em>termination) are used as nouns to the main verb. In this case, <em>participating </em>is the noun to the main verb <em>recall</em>. The function of this verbal is a direct object, because it is the thing being acted on by the verb. <em>Participating in a chess tournament</em> is what "receives" the action of the main verb.