Hi,
Which are the differences between "to speak"and "to talk"? When is it correct using "to speak" instead of"to talk"?
In general terms, 'speak' refers to the act of speaking while 'talk' refers to the giving of information. Some examples:
My English listening is OK, but my speaking is terrible.
Don't speak when you are eating.
I'd like to speak to that girl.
What were you talking to Mary about?
I want have a talk with you.
In practice, sometimes we don't much care which word we use. There's plenty of 'overlap'.
Best wishes, Clive