'do you speak..?' vs 'can you speak..?'

[je2ks2]

Hello, teachers. I'd like to know the difference in the meaning of two phrases 'Do you speak..?' and 'Can you speak..?'
In my language those are translated in pretty much same meaning, but I think there may be some differences. How do you ask when you want to find out that someone has ability or knowledge of another language (e.g, French)? Which one do you more commonly say--"Do you speak French?" or "Can you speak French?" I am very curious.....
I'll really appreciate your help. Thanks a lot in advance!

[engee30]

Hello, teachers. I'd like to know the difference in the meaning of two phrases 'Do you speak..?' and 'Can you speak..?'
In my language those are translated in pretty much same meaning, but I think there may be some differences. How do you ask when you want to find out that someone has ability or knowledge of another language (e.g, French)? Which one do you more commonly say--"Do you speak French?" or "Can you speak French?" I am very curious.....
I'll really appreciate your help. Thanks a lot in advance!

While asking about someone's ability to speak a particular language, you can use either.
Can you speak... could also be used if you wanted someone to speak to you in a particular language.