Choose the most suitable option to replace the highlighted part of the sentence:
He is good in mathematics.
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. is good at.
Grammar Rule: Prepositions after 'Good'
Specific prepositions are used to describe a person's proficiency or skill level in a particular subject or activity.
Good at is the standard idiom used to describe skill or ability. Whether it is an academic subject, a sport, or a hobby, 'at' is the correct preposition to use. For example, one might say someone is good at solving complex equations or good at analyzing economic trends.
Good in This is generally considered incorrect when referring to a specific skill or subject. While you might occasionally hear it in very casual conversation, it does not follow standard grammatical rules for proficiency. 'In' is typically reserved for physical locations or specific situations, such as being 'good in a crisis.'
Final Sentence: He is good at mathematics.