Okay so will probably notice that this is a second answer. I accidentally submitted the first one without finishing. I tried continuing it in a comment, but I did not like the format so let's give it a second try. Speak and talk pretty much the same and can be used interchangeably, the only difference is that "speak" is a bit more formal. They suggest that a person is using his or her voice, or that two or more people are having a discussion. But when you want to refer to someone's knowledge in a language you always use "speak" instead of "talk". Ex: She speaks three languages fluently. You would NOT say "She talks three languages fluently" "Tell" can be used in a number of different occasions (Let's look over some of them. 1. In cases of instruction. (Here you can replace tell with words like 'instruct' and 'inform') Ex: My professor told me how to fix the error. you can also say "My professor instructed/informed me how to fix the error." 2. To say someone told another to do something. Ex: My stupid brother told me to jump off the roof. 3. Never put the word 'it' after tell 4. When giving facts tell somebody (that) ... --------------------ex:She told me (that) she was ill. tell somebody something -----------------ex:She told me the news. tell somebody about something---------ex:Tell me about your new job. tell somebody who/when/where---------ex: He told me where it was. Say is used... 1. to say something someone said (sorry for using it in the definition but i couldn't avoid it) Ex: 1 He said "good morning" Ex: 2 She said Jim isn't coming tonight. 2. With this structure: say + something + to somebody. Ex: She said hello to me.

I can give you some examples and list which words would work in each example. 1. I would say that I haven't been to the lake enough this summer. Speak, tell, and talk do not work here. 2. Make sure you speak clearly when you give a lecture. Talk works here, but say and tell don't. 3. If I tell mom about last night, I'll be grounded for a month. say, speak, and talk don't work here. 4. Listen, we need to talk. Speak works here, but say and tell do not.

Speak and talk pretty much the same and can be used interchangeably, the only difference is that "speak" is a bit more formal. But when it you want to refer to someone's knowledge in a language you always use "speak" instead of "talk". Ex: She speaks three languages fluently. You would not say "She talks three languages fluently" "Tell" can be used in a number of different occasions.