In this English grammar error spotting question, read the sentence "The factory complex houses a shop-floor and 10 cubicles for the staff in an area of about thousand squares meters" and identify the part that contains an error, or mark that there is no error.

Introduction / Context:
Error spotting questions require you to pay close attention to articles, number forms, and correct noun usage. In this sentence about a factory complex and its built up area, the mistake lies not in the overall meaning but in the details of how the quantity and unit are expressed. Such questions are common in competitive exams because they test both grammar and a feel for natural English expressions.

Given Data / Assumptions:
• The full sentence is: "The factory complex houses a shop-floor and 10 cubicles for the staff in an area of about thousand squares meters." • Part A: "The factory complex houses a shop-floor". • Part B: "and 10 cubicles for the staff in an area". • Part C: "of about thousand squares meters." • Part D: "No error".

Concept / Approach:
In English, when we refer to a countable number like "thousand", we usually use an article or another determiner before it if it is singular and not part of a fixed phrase. We say "about a thousand square meters", not "about thousand square meters". Additionally, the unit should be "square meters", not "squares meters". This part of the sentence therefore contains two small but clear errors in article usage and plural formation. The rest of the sentence is structurally sound.

Step-by-Step Solution:
Step 1: Check Part A. "The factory complex houses a shop-floor" is grammatically correct. The verb "houses" correctly means "contains" or "accommodates". Step 2: Look at Part B. "and 10 cubicles for the staff in an area" correctly continues the description and links the second element with "and". No error here. Step 3: Examine Part C. The phrase should read "of about a thousand square meters." It is missing the article "a" before "thousand". Step 4: Notice that "squares meters" is also wrong. The correct form is "square meters", with "square" used as an adjective, not in plural form. Step 5: Since the error is clearly located in Part C, that part must be selected as the answer.

Verification / Alternative check:
Try rewriting the sentence in fully correct form: "The factory complex houses a shop-floor and 10 cubicles for the staff in an area of about a thousand square meters." This version sounds natural and follows standard English usage. If you compare this with typical descriptions in real estate advertisements or engineering reports, you will find the same structure repeated, which confirms that the revision is correct and the original Part C is faulty.

Why Other Options Are Wrong:
Part A is fine. The subject "The factory complex" and verb "houses" agree in number, and "a shop-floor" is an acceptable noun phrase. Part B is grammatically sound, linking the additional item "10 cubicles for the staff" and correctly using "in an area". Part D, "No error", is incorrect to choose, because we have clearly identified and corrected the issues in Part C.

Common Pitfalls:
Many learners overlook small articles like "a" and tend to focus only on bigger, more obvious grammar points. Another common mistake is treating measurement units as nouns to be pluralised blindly, leading to forms like "squares meters" or "litres waters". In technical and exam writing, such small errors can reduce clarity and correctness. To avoid them, pay attention to fixed collocations such as "square meter", "square kilometer", and revise them as complete chunks rather than as separate words.

Final Answer:
The part containing the error is "of about thousand squares meters." (Part C).