Is the sentence are talking to proper English?

The sentence "are talking to" is not a complete sentence in proper English. It is missing a subject.

Here are some examples of how to make it a proper sentence:

* "Are you talking to me?" (This includes the subject "you".)

* "They are talking to the teacher." (This includes the subject "they".)

* "We are talking to each other." (This includes the subject "we".)

To make it a grammatically correct sentence, you need to add a subject that performs the action of "talking to".