Correct Answer: B

Rationale: The sentence needs a comma before the conjunction 'but' to correctly join the two independent clauses 'The days seem long' and 'the nights seem even longer.' This comma helps to create a clear separation between the contrasting ideas in the sentence. Choice A (Period) is incorrect because a period would create two separate sentences rather than connecting them. Choice C (Colon) is incorrect as colons are used to introduce lists, explanations, or quotations. Choice D (Apostrophe) is incorrect as it is not needed in this sentence.

Correct Answer: C

Rationale: The word 'our' is the best substitute for the underlined words 'the doctor's and my' in the sentence. Using 'our' indicates joint possession, making the sentence more concise and natural. Choice A, 'his', is singular possessive and does not reflect the joint ownership implied by the sentence. Choice B, 'their', is plural possessive and does not align with the singular subjects 'the doctor and I'. Choice D, 'mine', is possessive for the first person singular pronoun and does not convey the shared ownership of the notes by both individuals.

Correct Answer: A

Rationale: The correct answer is 'and.' The sentence requires a conjunction that shows the need for both a thorough cleaning and washing the windows. The word 'and' is used to connect two actions that must be performed, indicating a list of tasks that should be completed in the lounge. Choices B, C, and D are incorrect because 'or' would imply a choice between cleaning and washing the windows, 'but' would suggest a contrast or contradiction between cleaning and washing the windows, and 'yet' is used to show a contrast or unexpected result, which is not suitable in this context where both actions are necessary.

Correct Answer: C

Rationale: The correct answer is C. The sentence requires an infinitive form of the verb 'to conduct' after the verb 'promised.' This structure is commonly used in English grammar, where the main verb 'promised' is followed by an infinitive verb form. Therefore, the sentence should read: 'The students promised to conduct themselves with quiet dignity.' Choice A ('conduct') is incorrect as it is not in the infinitive form required after 'promised.' Choice B ('conducting') is incorrect as a gerund does not fit the grammatical structure of the sentence. Choice D ('to be conducted') is incorrect as it changes the meaning of the sentence, suggesting that someone else will conduct the students, rather than the students conducting themselves.

Correct Answer: C

Rationale: The correct answer is 'C: herself.' In this sentence, 'herself' is the reflexive pronoun that correctly refers back to Mary Ann. It shows that Mary Ann is giving credit to herself for studying hard and passing the test. The use of 'oneself' (choice A) would be incorrect here as it is too general and does not specify Mary Ann. Choices B and D ('itself' and 'themselves') are also incorrect because they do not match the singular subject 'Mary Ann.' Therefore, 'herself' is the only option that fits both grammatically and contextually in this sentence.