Final answer:
The paragraph provided is free from the errors listed (a, b, c, d), and hence, no corrections are required for these points. The review questions demonstrate the proper use of commas, as commas should be used after introductory phrases, before conjunctions in compound sentences, or in lists. Subject and verb agreement are also crucial for clear communication.
Step-by-step explanation:
The paragraph provided does not contain the mistakes listed (a, b, c, d). Therefore, no corrections are needed for these particular points. This exercise appears to be a trap; the student needs to avoid making unnecessary changes when the text is already correct. The correct verb tense is used in 'I knew' for past events. The phrase 'to speak' is already in the correct form. The word 'situation' is singular and matches the context, and 'good person' is the appropriate singular term.
Reviewing the Review Questions for commas:
- I finally found my keys, and I got to work just in time.
- Mrs. Contreras threw out her old coffee table and cleaned the carpet.
- Taking the elevator to the roof, we hoped we could see the skyline and the bay.
- Though Susan wasn't feeling well, she went to the store anyway and bought ice cream, pizza, and candy.
- I let my neighbor borrow my phone because she said hers was tapped by the police.
For the planned exercise, it is crucial to examine each sentence individually for proper tense usage and ensure that the subject and verbs agree. Having a peer partner also helps contextualize verb forms within sentences that might alternate between past and present tense depending on the narrative.