Answer :
In the question sentence, the word "wind " acts as a simple subject and the word "was moaning " acts as a simple predicate.
What is Simple subject?
A simple subject is a single word or pronoun joined to a verb. The simple subject comes before the verb in most sentences. While there may be changes throughout the subject.
What is Simple Predicate?
A simple predicate is the main verb or verb phrase that describes the action of the sentence's subject. The leading verb or verb phrase is the only part that contributes to it being a simple predicate. The sentence contains no modifiers.
In this sentence given in the question "The wind in the trees was moaning eerily.", but since "was moaning" is a verb, it works as a simple predicate. Also, since the word "wind " is a noun or pronoun, it acts as a simple subject.
To learn more about simple subject, click below-
brainly.com/question/18735
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