Other answers are great. Does your mother speak English is the most subtle and polite.

Hello, "Can" asks whether she is able to speak English. "Does" asks whether she carries out the activity of speaking English. While the two sentences are grammatically correct, sentence 2 is more polite. I hope this answers your question. If you’d like to practice speaking. I’d be happy to help you develop a study plan. Feel free to view my teaching profile and class offerings and send me a message if you think I can help you. Regards.

They are quite similar. The first one emphasizes more on the ability of English speaking. And they are both grammatically correct and natural. You can use either of them.

Hi. Almost no difference between these two. The first one is about whether she Can And the second one can mean two things: Can she? Does she do it usually?