The CEO was convinced that the legal advice was wrong, and he made sure that everyone knew that he did not think so. A. everyone knew that he did not think so. B. everyone knew that he thought not. C. everyone knew that he doubt it. D. everyone knew that he did think so. E. everyone knew that he thought so

Critical reasoning is essential for GMAT sentence correction tasks. It involves understanding the logical flow of the sentence and the argument being made. In this exercise, the main idea is that the CEO disagreed with the legal advice.
When you break down sentence choices, ask yourself: Does this option clearly convey the CEO's disagreement? For example, Option A ('everyone knew that he did not think so') clearly shows the CEO's opposition to the advice.
Other options (B, C, D, and E) fail to communicate this main idea, either due to incorrect grammar or poor wording. Critical reasoning helps you eliminate these choices and find the best fit, ensuring clarity and logical consistency.

Understanding grammar rules is crucial when comparing sentence options in GMAT sentence correction exercises. First, consider subject-verb agreement, verb tense consistency, and pronoun clarity.
In our exercise, Option A is grammatically correct: 'everyone knew that he did not think so.' It matches subject-verb agreement ('everyone knew') and accurately uses the past tense ('did not think').
Options B and C break grammatical rules. 'He thought not' (Option B) and 'he doubt it' (Option C) have awkward or incorrect verb structures. Option D ('he did think so') negates the earlier part of the sentence and confuses the meaning. Option E might appear grammatically correct, but it lacks the clarity needed in context.
So, always analyze each sentence option for proper grammar usage to eliminate inappropriate choices.

Sentence structure involves the arrangement of words to create clear and coherent sentences. Good structure follows standard syntactic rules, ensuring that the sentence is easy to understand and reflects the intended meaning.
In our example, the CEO wanted everyone to understand his disagreement. 'Everyone knew that he did not think so' (Option A) is structured correctly for clear communication. It uses a dependent clause ('that he did not think so') to explain what everyone knew.
Options B and C display poor sentence structure with awkward wording or incorrect forms, making them difficult to understand. Option D contradicts the meaning of the initial statement, while Option E lacks precision due to its ambiguous use of 'so.'
Prioritizing proper sentence structure ensures your message is delivered effectively and aligns with the grammatical and logical points discussed in critical reasoning and grammar analysis.