which sentence contains a predicate noun?
Hoover will lead the group hike on sunday
He plans to leave Lookout Point
He is an expert on the plants of the region
He tells hikers about animals too
To have a predicate noun in a sentence, you must also have a linking verb, not an action verb. So look at the verbs and decide which one is the linking verb:
will lead
plans
is
tells
http://grammar.ccc.commnet.edu/grammar/verbs.htm#linking
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