Correct Answer: B

Rationale: In the given sentence, the word 'once' is used incorrectly. The original sentence implies that the professor was an intern in the hospital at a specific time in the past, not just once. The word 'formerly' would imply that the professor used to be an intern but is no longer. Therefore, 'once' is the incorrect word choice in this context. The other options ('professor,' 'intern,' 'hospital') are all used correctly in the sentence.

Correct Answer: C

Rationale: The phrase 'had rarely' is not used correctly in the sentence. The correct form should be 'rarely eaten' instead of 'had rarely' to convey the past tense of the children's eating habits before their hospitalization. 'Had rarely' is incorrect because it does not match the structure needed to describe the children's eating habits in the past. Choices A, B, and D are grammatically sound and fit appropriately in the sentence.

Correct Answer: D

Rationale: The word 'although' is the best fit in the sentence because it indicates a contrast between the fact that the emergency room was not busy last night and the head nurse's decision not to let anyone end her shift early. 'Although' sets up a contrast by acknowledging the first part of the sentence while introducing the surprising or unexpected information that follows. Choices A, B, and C do not provide the appropriate contrast needed in this context. 'Because' implies causation, 'Provided that' implies a condition for something to happen, and 'As if' implies a comparison rather than a contrast.

Correct Answer: C

Rationale: In this sentence, we are looking for a pronoun that refers to more than one person. The children and 'them' performed a skit for the elderly patients. 'Them' is the correct pronoun to use in this context to indicate a group of people, which is the plural form of the pronoun. Choice A, 'he,' is singular and would not match the plural subject. Choice B, 'me,' is an object pronoun and does not fit the subject position. Choice D, 'her,' is singular and does not agree with the plural subject 'children and them.' Therefore, the correct answer is 'C: them.'

Correct Answer: C

Rationale: The phrase 'and new tires' is misplaced in the sentence as it disrupts the flow of information. It introduces unnecessary detail that does not directly contribute to the main point of the sentence, which is identifying the ownership of the car. Choices A, B, and D are all essential parts of the sentence that help convey the location of the car and its ownership, making them correctly placed within the sentence.