In the second sentence, the phrase "inside his trouser pockets" is a/an?

Look up the word "inside" to learn what part of speech it is. This should be a big clue.

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In the given sentence, the phrase "inside his trouser pockets" is a prepositional phrase. It functions as an adverbial phrase, providing additional information about the location of something.

To identify the phrase, you can break down the sentence and analyze its components:

1. Subject: "he"
2. Verb: "kept"
3. Direct Object: N/A
4. Prepositional Phrase: "inside his trouser pockets"

The prepositional phrase begins with the preposition "inside" and includes the object of the preposition "his trouser pockets." It specifies where the action of the verb is happening, indicating the location of what the subject is keeping.