Improvement of sentence: a part of the following sentence is considered incorrect. Choose the alternative that best improves the sentence. If no improvement is needed, choose the option marked No improvement. Sunil and I helped to sell tickets.

Introduction / Context:
This question focuses on correct use of pronouns and sentence structure in English. It asks you to improve the sentence Sunil and I helped to sell tickets. Sentence improvement questions often test whether you can replace a whole phrase with a more natural and grammatically correct alternative.

Given Data / Assumptions:

• Original sentence: Sunil and I helped to sell tickets.
• The underlined part is likely Sunil and I.
• Options are we helped to sell tickets, us helped to sell tickets, me helped to sell tickets, and No improvement.
• The meaning should remain that both the speaker and Sunil took part in selling tickets.

Concept / Approach:
In English, a full noun phrase like Sunil and I can often be replaced by the pronoun we, when both people are included. The subject pronoun we is grammatically correct at the beginning of a sentence. The forms us and me are object pronouns and cannot be used as the subject in standard English. So the best improvement is to use we helped to sell tickets.

Step-by-Step Solution:
Step 1: Recognise that Sunil and I together act as the subject of the verb helped. Step 2: Identify the correct subject pronoun that replaces Sunil and I, which is we. Step 3: Replace Sunil and I with we and keep the rest of the sentence unchanged: we helped to sell tickets. Step 4: Check that the new sentence is shorter, clearer, and grammatically correct.

Verification / Alternative check:
Compare the sentences: Sunil and I helped to sell tickets and We helped to sell tickets. Both have the same meaning, but the second is more concise and natural. English style often prefers a pronoun when the context is clear. This confirms that the improved version with we is acceptable and even better.

Why Other Options Are Wrong:

• us helped to sell tickets: Uses the object pronoun us as a subject, which is grammatically incorrect.
• me helped to sell tickets: Me is also an object pronoun and cannot be used as the subject.
• No improvement: The original is not wrong in meaning, but the question expects the best improvement, which is we helped to sell tickets.

Common Pitfalls:
Many learners are confused about I and me, and sometimes even use me and Sunil as the subject. Others think that if a sentence is not completely wrong, they should choose No improvement. In sentence improvement questions, you must choose the most effective and grammatically correct version, not only avoid errors.

Final Answer:
Correct option: we helped to sell tickets.