Understanding Grammatical Errors in Sentences

The question asks us to identify the segment in the given sentence that contains a grammatical error. The sentence is: "If there had not been such a long queue I could have returned back by 11 am." Let's examine each segment provided in the options to pinpoint the error.

Analyzing Each Sentence Segment

We will go through each part of the sentence as broken down by the options and check its grammatical correctness.

• Segment 1: "If there had not been"
  This is the 'if' clause of a conditional sentence. The structure "If + past perfect" (had not been) is appropriate for a Type 3 conditional, which talks about a hypothetical situation in the past and its past consequence. This segment appears grammatically correct in this context.
• Segment 2: "such a long queue"
  This phrase modifies the noun 'queue'. 'Such a' is used to indicate a degree or kind. "Such a long queue" is a standard and grammatically correct phrase used to describe the queue. This segment is correct.
• Segment 3: "I could have returned back"
  This is the main clause of the conditional sentence. The structure "could have + past participle" (could have returned) is also correct for the main clause of a Type 3 conditional, indicating a possible consequence in the past. However, the word "back" after "returned" is redundant. The verb 'return' already means to come or go back to a place. Using "returned back" is a common error known as pleonasm or redundancy. This segment contains a grammatical error.
• Segment 4: "by 11 am"
  This phrase specifies a time by which the action could have occurred. The preposition 'by' is correctly used here to indicate a deadline or a specific time point. This segment is grammatically correct.

Identifying the Grammatical Error

Based on our analysis, the error lies in the phrase "returned back". The word 'back' is unnecessary and makes the phrase redundant because 'returned' already implies going back.

Therefore, the segment containing the grammatical error is "I could have returned back".

Revision Table: Common Redundancies

Understanding common redundant phrases can help identify grammatical errors quickly.

Additional Information: Type 3 Conditional Sentences

The sentence uses a Type 3 conditional structure, which is used to talk about hypothetical situations in the past and their unreal past consequences. The structure is:

If + Past Perfect (had + past participle), Would/Could/Might have + Past Participle

In the given sentence:

• If clause: "If there had not been such a long queue" (If + past perfect)
• Main clause: "I could have returned back by 11 am" (Could have + past participle + redundancy)

The structure of the clauses themselves (Past Perfect in 'if' and Could have + Past Participle in the main) is correct for a Type 3 conditional, but the inclusion of 'back' introduces the grammatical error of redundancy.