This is a conversation between two friends, one is 30 the other is 25. They are speaking about their school time:
A: Do you remember Mr. X? He was my English teacher.
B: Oh, yes. He was my English teacher too.
I want to use "so" or "too" in a short sentence (B's sentence) to show agreement with a positive statement.
I know if the conversation was as follows, I could use "I was too." or "So was I":
A: Do you remember Mr. X? I was his student.
B: Oh, yes. I was his student too./ I was too./ So was I.(And informally: Me too./ Ditto.)
But I don't know how B can use this grammar to express their agreement with A, in the first conversation.
If this grammar is not applicable to the first conversation, how should B express their agreement (i.e. "That's also true for me.") in a short form? (formally or informally)