oral, spoken, conversation

[Ju]

1. She is an English teacher specialised in oral English.
2. She is an English teacher specialised in spoken English.
3. She is an English teacher specialised in English conversation.

Which of the above sentences is correct?

Thank you.

[bhaisahab]

1. She is an English teacher specialised in oral English.
2. She is an English teacher specialised in spoken English.
3. She is an English teacher specialised in English conversation.

Which of the above sentences is correct?

Thank you.

They would all be OK with "specialising in" instead of "specialised in".