Student or Learner
1) John went to the table where Mary was sitting and sat opposite to her.
2) John went to the table where Mary was sitting and sat opposite her.
Can someone please tell me which of the above two sentences is correct?
The second one is correct.
Merriam-Webster's Learner's Dictionary
on the other side of (something or someone) : across from (something or someone)
▪ He sat opposite me.
▪ She lives in the house opposite ours.
▪ The school is opposite a park.
▪ I played opposite the best player in the league.