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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