Correct preposition: I am strong in/at English.

English as a Second Language English Vocabulary, Grammar and Idioms
1
  1. I am weak in/at Maths.
  2. I am strong in/at English.

Which preposition should I use in each of the sentences?

Thanks in advance.

2

You can use either preposition. It doesn’t matter which one. The sentence will mean the same thing.