Introduction / Context:
In this error-spotting question, we are checking the correct use of conditional perfect constructions and active/passive voice in formal written English. The focus is on how past unreal conditions are expressed and how the auxiliary sequence should be formed when a passive meaning is intended.
Given Data / Assumptions:
- The sentence is: "They could have helped him had they approached by him for help well in advance."
- We must find which underlined part (A–D) contains the error; option E means no error.
- Register is standard formal English.
Concept / Approach:
The structure "could have + past participle" expresses past ability/opportunity not realized. The clause starting with "had" is the inverted form of "if + past perfect," e.g., "Had he approached them..." For a passive meaning with "approach," the correct passive perfect requires "been approached": "had they been approached by him." Without "been," the phrase is ungrammatical.
Step-by-Step Solution:
1) Identify the conditional pattern: "They could have helped him had ..." indicates a past unreal/remote condition.2) Check the verb form after "had": It should be past perfect (active) or past perfect passive.3) The fragment "had they approached by him" lacks the auxiliary "been" required for passive perfect.4) Correct passive: "had they been approached by him..." (or better active alternative: "had he approached them...").5) Therefore, the error lies in part C.
Verification / Alternative check:
Rewrite actively: "They could have helped him had he approached them well in advance." This is idiomatic and grammatical. If you prefer passive, include "been": "had they been approached by him."
Why Other Options Are Wrong:
A: "They could have" correctly starts a conditional perfect result clause.B: "helped him" is a correct past participle phrase complementing "could have."D: "for help well in advance" is acceptable as an adverbial phrase of time and purpose.E: "No error." is incorrect because part C has a form error.
Common Pitfalls:
Students often omit "been" in passive perfect forms after "had." Another pitfall is mixing active and passive participants (e.g., "they approached by him") which yields a broken structure. Also watch the inversion "Had + subject + past participle" as a substitute for "If + subject + had + past participle."
Final Answer:
had they approached by him
Discussion & Comments