In the following sentence, one part may contain a grammatical error. Identify the part with an error, if any, in "My lawn which is overgrown needs weeding."

Introduction / Context:
This error spotting question presents a sentence divided into three parts plus a "No error" option. The sentence is "My lawn which is overgrown needs weeding." You must decide whether any portion of this sentence violates standard grammar or whether it is entirely correct. Such questions check your familiarity with relative clauses, subject verb agreement, and basic sentence structure.

Given Data / Assumptions:

Full sentence parts:
Part A: "My lawn"
Part B: "which is overgrown"
Part C: "needs weeding"
Part D: "No error"
We assume formal standard English.
The phrase "which is overgrown" functions as a relative clause giving more information about the lawn.
We must check agreement and overall sentence completeness.

Concept / Approach:
The sentence describes the speaker's lawn, adds a descriptive clause about it being overgrown, and then states that it needs weeding. A grammatically correct structure would be: subject ("My lawn"), relative clause ("which is overgrown"), and main verb phrase ("needs weeding"). The verb "needs" agrees with the singular noun "lawn", and the non finite "weeding" correctly expresses the required action. There is no tense error, no article issue, and no problem with the relative pronoun "which". Therefore there is no error in any part of the sentence.

Step-by-Step Solution:
Step 1: Check Part A, "My lawn". This is a clear singular noun phrase with possessive determiner "my". There is no grammatical problem. Step 2: Check Part B, "which is overgrown". This is a relative clause introduced by "which", referring back to "lawn". The verb "is" correctly matches the singular subject "lawn", and "overgrown" is a suitable adjective. Step 3: Check Part C, "needs weeding". The singular subject "lawn" requires "needs", not "need", so subject verb agreement is correct. The gerund "weeding" appropriately expresses the action required. Step 4: Combine all parts: "My lawn which is overgrown needs weeding." The sentence is complete, meaningful, and grammatically sound. Step 5: Conclude that no part contains an error, so the correct answer is the "No error" option.

Verification / Alternative check:
We can also rewrite the sentence slightly to check structure: "My lawn, which is overgrown, needs weeding." Adding commas around the relative clause makes it non restrictive but does not change grammar. Both versions are acceptable. Furthermore, if there were an error, it might relate to the choice of "which" versus "that", but in modern English both relative pronouns are acceptable here. None of the parts show issues with tense, agreement, or word form. This confirms that the sentence is correct.

Why Other Options Are Wrong:
Option A is not the error because "My lawn" is a standard noun phrase.
Option B is not the error because "which is overgrown" is a correctly formed relative clause giving extra information.
Option C is not the error because "needs weeding" correctly expresses what should be done to the lawn.
Therefore options A, B, and C are all grammatically sound, making "No error (Part D)" the correct choice.

Common Pitfalls:
Some students overthink relative clauses and suspect an error where none exists, for example by imagining that "which" must always be replaced by "that". Others may feel that a comma is missing and mark an error even though punctuation is not the focus in such grammar questions. In most exam patterns, absence of optional commas is not treated as a grammar error unless punctuation is explicitly tested. Always check for clear violations like wrong tense, wrong number agreement, or incorrect verb form before assuming an error in a well formed sentence.

Final Answer:
No error (Part D)