Answer:
14. Us- object of preposition
15. They- subject
16. Us- direct object
17. We- apposition to the subject.
Step-by-step explanation:
14. Janice brought a big surprise for us.
The pronoun in this sentence is "us', used as an object of preposition. Prepositions are those words that identify the position of the noun or pronouns in the sentence. Objects of prepositions are those nouns/ pronouns that follows a preposition and completes the sentence.
15. They were thrilled to win first prize.
The pronoun in this sentence is "they" and it is being used as a subject in the sentence. The subjects of a sentence are those nouns or pronouns that do the main action.
16. The contest judges praised us.
The pronoun in this sentence is "us" and it is being used as a direct object. Direct objects those nouns or pronouns that are directly addressed in the sentence, the recipient of the action that is being done by the subject or the verb.
17. We contestants are a determined bunch.
In this sentence, the pronoun is "we" and it is being used as an apposition to the subject. Appositions are those words that rename/ changed the original noun/ pronoun but still representing the noun/ pronoun in the sentence.