When I was going through "Common Mistakes in English" (Longman), I saw the following:
Good at, not in. Don't say: My sister's good in maths. Say: My sister's good at maths.
But I saw the following on one Site:
When it comes to school subjects, both “good at” and “good in” are used Jere is good at math: he always finishes first. Jere is good in math: he makes all A’s.
Please clarify which one is correct nowadays....
Top answer
Language changes over time. Longman is traditional, and you can't go wrong following their guidelines. When you take a grammar test, go traditional.
— AlpheccaStars
Language changes over time.
Longman is traditional, and you can't go wrong following their guidelines.
When you take a grammar test, go traditional.
But "in" is OK in modern conversations.
Perhaps a newer edition of Longman will reflect this change.
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Language changes over time. Longman is traditional, and you can't go wrong following their guidelines. When you take a grammar test, go traditional. But "in" is OK in modern conversations. Perhaps a newer edition of Longman will reflect this change.
It's possible also that there are regional and/or personal differences. For me, "My sister's good in maths" seems unacceptable if "maths" means the subject. It may be feasible if "maths" means "maths classes".