Improve the bracketed part of the sentence by choosing the correct option: "Both the families were invited but neither (had accepted) our invitation."

Introduction / Context:
This is a sentence improvement question that focuses on subject verb agreement and tense usage with the word "neither". The sentence describes a past completed action related to two families who were invited but did not respond positively. You must choose the verb form that best completes the sentence in standard English.

Given Data / Assumptions:

• Original sentence: "Both the families were invited but neither had accepted our invitation."
• Part in brackets: "had accepted".
• Options: accepted, did accept, has accepted, no improvement.
• Context: past event of invitation and non acceptance.

Concept / Approach:
The main clause "Both the families were invited" uses simple past tense ("were invited"). The contrasting clause introduced by "but" should also be in simple past tense to maintain consistency, unless there is a strong reason to emphasise a prior past action with past perfect ("had accepted"). Here, there is no earlier past event that requires past perfect. Therefore, simple past "accepted" is the appropriate choice.

Step-by-Step Solution:
Step 1: Identify the tense of the first part: "were invited" is simple past. Step 2: Notice the connector "but neither" which introduces a contrasting action that took place in the same time frame. Step 3: Examine "had accepted" (past perfect). Past perfect is normally used when one past action happened before another past action. In this sentence, there is no clear sequence of two different past times; we only know that they did not accept. Step 4: Consider "accepted" (simple past). "Neither accepted our invitation" matches the time frame of "were invited" and is straightforward. Step 5: Consider "did accept". This form is usually used for emphasis or questions, such as "Did they accept?" or "They did accept our invitation." It sounds unnatural in this negative contrast. Step 6: Consider "has accepted" (present perfect). This tense connects past actions to the present, which does not fit a narrative that is clearly about a completed past event. Step 7: Conclude that "accepted" is the best replacement, giving: "Both the families were invited but neither accepted our invitation."

Verification / Alternative check:
Compare two versions: Incorrect: "Both the families were invited but neither had accepted our invitation." Correct: "Both the families were invited but neither accepted our invitation." The correct version sounds natural and consistent in tense. The incorrect version uses past perfect unnecessarily, which exam setters often treat as an error in such contexts.

Why Other Options Are Wrong:
Option (B) "did accept" seems forced and would be more appropriate if we were emphasising acceptance rather than non acceptance. Option (C) "has accepted" would be used if the acceptance had relevance to the present, which is not indicated. Option (D) "no improvement" fails because the original "had accepted" does not suit the context.

Common Pitfalls:
Learners sometimes overuse past perfect ("had" plus past participle) in any sentence referring to the past, without checking whether two distinct past time points are involved. In exam questions, simple narratives about one past event usually stay in simple past. Another pitfall is ignoring the influence of contrast words such as "but" that link actions in the same time frame. Always match tenses logically instead of choosing the most complicated form.

Final Answer:
The bracketed phrase should be replaced with "accepted", so the sentence reads: "Both the families were invited but neither accepted our invitation."