may we talk in skype for practing oral english？

I would suggest a website called conversationexchange.com. I have had good luck finding language partners (you speak 1/2 of the time in their language, and 1/2 in yours).

It is best to find someone who wants to learn your language, that way it is an equal exchange.

By the way, we don't use the phrase "oral english". Let me offer a different wording.

Could we talk in Skype to practice spoken English?

Dear, thank you for your advise. It is great helpful for me.I will try to register in the website to find a parter.

skype, although getting better, still misses the visual cues in word pronunciation because the visual and audio are never in synch.

I've been using Skype for years and I've never seen a problem with speech and video not being in synch. Nor has anyone I've known mentioned that problem. Maybe I'm missing something? or maybe there's a bandwidth problem somewhere?

I use skype and it works out well.
I can imagen that teaching would be fine too. I think it would even be fun to do it per skype.