Improve the bracketed part of the sentence or select "No improvement":\n"A small makeshift stage (was construct) with a red curtain for a backdrop."

Introduction / Context:
This sentence improvement question checks your understanding of tense, voice, and correct past participle forms in passive constructions. The sentence describes an action completed in the past: building a makeshift stage with a red curtain. The bracketed phrase "was construct" is grammatically wrong, and you must choose the correct replacement or confirm if no change is needed.

Given Data / Assumptions:

• Full sentence: "A small makeshift stage (was construct) with a red curtain for a backdrop."
• The subject "A small makeshift stage" is singular.
• The intended sense is that someone constructed the stage in the past.
• Options provide variants of the verb phrase and a "No improvement" choice.

Concept / Approach:
The key concept is the passive voice in the past simple tense. The standard form in English is "was" or "were" plus the past participle of the main verb. Here, "construct" is the base form, and its past participle is "constructed". Because the subject "stage" is singular and the action is completed in the past, the correct passive form should be "was constructed". We must also check subject–verb agreement and tense consistency.

Step-by-Step Solution:
Step 1: Identify the structure. The sentence does not mention who built the stage, so passive voice is appropriate: "was constructed".Step 2: Replace "construct" with its past participle "constructed". The correct passive form is "was constructed", not "was construct".Step 3: Compare option (a): "are constructed". This is present tense plural and does not match the singular subject "stage" or the past time reference.Step 4: Compare option (b): "was constructed". This is past simple passive and agrees with the singular subject.Step 5: Compare option (c): "were constructed". This is past simple passive but plural; it does not agree with "A small makeshift stage".Step 6: Note that option (d) "No improvement" would keep the incorrect form "was construct", so it must be rejected.

Verification / Alternative check:
Substitute option (b) into the full sentence: "A small makeshift stage was constructed with a red curtain for a backdrop." This reads smoothly and clearly indicates a completed action in the past. If we try the other options, "A small makeshift stage are constructed" is ungrammatical, and "were constructed" clashes with the singular subject. Therefore, only "was constructed" meets all grammatical requirements.

Why Other Options Are Wrong:

• Option (a) "are constructed": Present tense and plural; incorrect for a single stage described as already built.
• Option (c) "were constructed": Past tense but plural; does not agree with the singular subject "stage".
• Option (d) "No improvement": Retains the incorrect form "was construct", which lacks the past participle.

Common Pitfalls:
Students sometimes overlook the need for a past participle after "was" or "were" and wrongly treat the base verb as acceptable. Another common mistake is focusing only on tense and ignoring subject–verb agreement, which leads to choices like "were constructed" with a singular subject. To avoid such errors, always ask: what is the subject, what is the time reference, and does the verb form match both voice and number?

Final Answer:
The correct improvement is "was constructed", so the sentence should read: "A small makeshift stage was constructed with a red curtain for a backdrop."