Now you have me thinking about it. I suppose a good way is to review in the mind what communication is-- or should be: just a transfer of an idea or meaning from one person, through speech, across a distance (and maybe across time also) to another person that receives the communication-- and hopefully understands it. These four verbs emphasize different parts of this communication process. Tell-- emphasizes WHAT was said by one person to another. There is what has become an expression of surprise after hearing someone say something; "Do tell!". Originally, and to some extent today still, it means that the listener wants to hear more about the subject they just heard. Speak-- emphasizes just the speaker saying something, but no reference about who is listening or if the listeners are understanding. If fact a person could be speaking to themselves. Also the speaker can be speaking to multiple listeners-- then you have a speech. Say-- like Tell, but a little lighter, less formal. There is not so much emphasis on WHAT was said, but there is still some emphasis. Talk-- this is the only one of the four verbs that fully includes both parties to the conversation. Talk means two-way conversation. The other three refer to just a one-way communication. With talk the emphasis is on the fact of communication rather than what the communication was about-- but you can change that if you add a phrase like "talk about where we want to go on vacation". Chatting is a verb similar to Talk, but it is always less formal.

- tell: give the information about something. example: tell me about your story,please. - speak: say something in order to convey information or to express a feeling. example: can you speak English? - say: speak or tell something example: how do you say that word? - talk: say or discuss something. example: she talked on the phone last night. you may open this link: http://www.oxforddictionaries.com/definition/english/talk?q=talk

Watch: http://www.engvid.com/talk-speak-tell/