Locate the gerund phrase and identify its noun use. A popular pastime for retirees is camping near a lake.

Gerund Phrase:

Noun Use:

In the sentence "A popular pastime for retirees is camping near a lake", the gerund phrase is "camping near a lake" and its noun use or nominal function is Subject complement, since the verb of the clause "is" is a linking verb that requires a subject complement, that is, a group of words that gives information about the subject.