Ich spreche mit dir. (informal, singular, dative)
Ich spreche mit Ihnen. (formal, singular, dative)
I only answer because you have not had a German native answer, and I have noticed that German native speakers seem to be harder to come across here than other language speakers. It is almost as though they have realized that they are holding the analytical high ground and want to conserve their resources. I would not fully trust a Chinese to correct me in German, unless I could see more of his work. I have seen Chinese that are much better than I am with German, though.
I am American but have been to Germany and have studied German for a few years.