Improve the bracketed part of the sentence by choosing the best alternative: I wish I (was) a superman.

Introduction / Context:
This sentence improvement question tests your understanding of the English subjunctive mood, which is used to talk about wishes, unreal situations and hypothetical conditions. The sentence expresses a wish about something that is contrary to fact: the speaker is not actually a superman. Standard grammar in such cases prefers I wish I were rather than I wish I was.

Given Data / Assumptions:
Sentence: I wish I (was) a superman.
Bracketed part to improve: was.
Options: am, have been, were, No improvement.
We assume the speaker is imagining an unreal situation in the present or future, not talking about a real past event.

Concept / Approach:
In formal and examination English, when we express an unreal or hypothetical situation after I wish, we use the past subjunctive form were with all subjects, including I and he or she. This is similar to If I were rich or I wish he were here. Although many native speakers informally say I wish I was, exams still treat were as the correct and more formal form. Therefore, we must replace was with were in the sentence I wish I were a superman.

Step-by-Step Solution:
Step 1: Recognise that the sentence uses I wish, signalling a desire about a situation that is not true at present. Step 2: Recall the rule: after I wish or if in unreal, present time conditions, we use were with singular subjects to show that the situation is imaginary. Step 3: Check option am. I wish I am a superman is wrong because am refers to the present reality, not an unreal wish. Step 4: Check option have been. I wish I have been a superman is wrong in tense and meaning; have been points to completed past time, not an unreal present wish. Step 5: Check option were. I wish I were a superman follows the rule of the subjunctive and correctly marks the situation as hypothetical. Step 6: No improvement cannot be correct because was is not the exam standard in this context. Therefore, were is the best improvement.

Verification / Alternative check:
Compare similar sentences: I wish I were taller, I wish it were Sunday, If I were the prime minister. These are classic textbook examples of the subjunctive used for unreal present or future situations. Replacing were with was in such sentences is often marked as incorrect in formal examinations. The same pattern applies to I wish I were a superman, confirming that option were is the correct choice.

Why Other Options Are Wrong:
Am indicates a real present state, which contradicts the idea of wishing for something that is not true now.
Have been indicates a completed action or state in the recent past and does not match the structure of wishes about current impossibilities.
No improvement would keep was, which is widely considered less formal and is not the standard expected in competitive exams testing the subjunctive mood.

Common Pitfalls:
Because many native speakers say I wish I was, learners sometimes think this is acceptable in all contexts. Exams, however, stick to traditional grammar rules and expect were with I, he, she, and it in unreal conditional or wish sentences. To remember this, associate I wish with If I were, not If I was, and you will consistently choose the correct option in tests.

Final Answer:
The correct improvement is were, giving: I wish I were a superman.