speak vs. talk

Would native speakers use all the following sentences?

If so, is there a difference in meaning between them?

(a) I heard them speaking Scotch dialect.
(b) I heard them speaking in Scotch dialect.
(c) I heard them talking in Scotch dialect.

Thanks in advance.

Hirashin

There is no significant difference in meaning, but we need to change "Scotch dialect" to "Scottish dialect".

In some other situations "talk" and "speak" can have slightly different nuances, which you can read about to your heart's content if you Google for "difference between talk and speak".

I wouldn't use any of them.

First of all, when I would always use "speak" when describing how someone is verbally using a language.

To me, "talking" strictly means, "having a conversation." For example:
Let me talk with you.
We were talking for hours.
Did you talk to her?

In the above examples, I could use "speak" interchangeable with any of the "talks", but it doesn't sound as natural.
Let me speak with you. (sounds pretty natural)
We were speaking for hours. (doesn't sound too natural)
Did you speak to her? (sounds somewhat natural)

If I'm describing how someone verbally uses a language, I always use speak:
He spoke with an accent.
He speaks very well.

Using "talk" instead sounds very unnatural, and also low class!
He talks with an accent. (not very natural)
He talks very well. (not natural)

In your examples, I would say, "I heard them speaking with a Scotch dialect."

ClarkH said:

To me, "talking" strictly means, "having a conversation."

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I understood all the original sentences to be describing overhearing a conversation.

eeky said:

I understood all the original sentences to be describing overhearing a conversation.

Click to expand...

Me too.

Hirashin overheard them having a conversation, but then he is describing the way they verbally use the language.

Thanks for your help, eeky and ClarkH.

I have a question for eeky. How do you use the words Scotch and Scottish?
I have often heard "Scotch whisky", not "Scottish whisky". Do you ever say
"Scottish whiskey" as well?

Hirashin