In the following English grammar error spotting question, identify which part of the sentence contains a grammatical error: "The plane was too far away that it was just a dot in the sky."

Introduction / Context:
This question checks your understanding of English grammar related to degree expressions, specifically the correct use of patterns such as "too ... to" and "so ... that". Competitive examinations frequently test such subtle differences in structure because they strongly affect sentence correctness and clarity. The sentence given is "The plane was too far away that it was just a dot in the sky." You must choose which labeled part of the sentence contains the grammatical error. At first glance the sentence may feel almost natural in everyday speech, but standard written English requires a precise connector after "too", and that is where the problem lies.

Given Data / Assumptions:

• The full sentence is: The plane was too / far away that it was / just a dot in the sky.
• Part A: "The plane was too"
• Part B: "far away that it was"
• Part C: "just a dot in the sky."
• Part D states that there is no error in the sentence.
• We assume standard formal English usage as required in exams.

Concept / Approach:
In English grammar, "too" is generally followed by an adjective or adverb, and the usual pattern is "too + adjective/adverb + to + verb". For example, "too far away to see" or "too tired to continue". When we want to use "that", the correct pattern normally is "so + adjective/adverb + that + clause", as in "so far away that it was just a dot". Mixing "too" with "that" creates an incorrect and unidiomatic structure in formal English. Therefore, we need to locate the part of the sentence where this incorrect combination appears. The error is not with the idea itself but with the grammatical structure chosen to express that idea.

Step-by-Step Solution:
Step 1: Read the entire sentence for general sense: it clearly means that the plane was at such a great distance that it appeared only as a dot in the sky. Step 2: Focus on the structure "too far away that". Here, "too" is correctly placed before the adjective "far", but the connector after it should be "to" plus a base verb, not "that". Step 3: Consider correct patterns. We could say "The plane was too far away to see clearly" or "The plane was so far away that it was just a dot in the sky." Step 4: Because the sentence uses "too far away that", we can see that the combination "far away that it was" is the erroneous portion. Step 5: This entire faulty structure lies in part B, so part B is the one that contains the error.

Verification / Alternative check:
A quick way to verify is to rewrite the sentence correctly in both possible correct patterns. Option 1: "The plane was so far away that it was just a dot in the sky." This uses "so ... that" and sounds natural and correct. Option 2: "The plane was too far away to be seen clearly." This uses "too ... to" and again is fully correct. In both correct versions, the problematic stretch "too far away that" disappears, which confirms that the error is precisely where "too" is wrongly followed by "that". Since that part is contained in segment B, our choice is consistent and reliable.

Why Other Options Are Wrong:
Part A – "The plane was too" is grammatically fine, because "too" can appropriately precede an adjective or adverb as long as the remaining pattern is correct. Part C – "just a dot in the sky." is a perfectly natural and correct phrase describing how the plane looked. The option "No part has an error" is wrong because we have clearly identified an incorrect structure that does not follow standard rules. The option stating that both A and B together are wrong is incorrect because only the "far away that it was" portion creates the ungrammatical combination with "too"; the words in part A function correctly once part B is repaired.

Common Pitfalls:
Many learners confuse "too ... to" and "so ... that", sometimes blending them in exams because in casual speech people may not notice the difference. Another common mistake is to assume that if a sentence feels understandable, it must be grammatically acceptable, which is not always true. In formal writing and competitive examinations the exact connector after "too" is important. Students also sometimes overfocus on vocabulary such as "dot in the sky" and miss the structural issue earlier in the sentence. Remember to always check the pattern around degree words like "too", "so", "very", and "enough".

Final Answer:
The part containing the error is Part B – "far away that it was", because the sentence should use either "so far away that" or "too far away to", not "too far away that".