Thinking in terms of context rather than grammar, the person is stressing that they like someone who thinks otherwise. So the conversation would be: Girl: You don't really like me Boy: I DO, I DO like you ... really (ie., it's true despite what you think) Here it seems that 'really' doesn't mean "a lot" as in "I really like you" = "I like you a lot" but rather, "it's true/a fact that I like you". So, if the guy wants to contradict the girl, and then emphasise that he likes her a lot he would say: Boy: "I *do* like you, really. I *really* like you. The first and the second sentence do not mean the same: (1) It is a true (real) fact that I like you, depite what you think; (2) In addition, I like you a lot. To avoid confusion, it would be better to say (what would mean the same): "In fact, I *do* like you. I like you *a lot*" It's important where you put the *stress*. The point is I guess that "really" is ambiguous between (1) "a lot", eg., the movie was really good, and (2) "it's true despite what you think/believe", eg., you don't believe me, but it's true, he really kissed her at the party.

benni, 1) I really do like you. 2) I do really like you. Both these variants are possible in English. There is no way to tell the exact meaning of 'really' in these sentences without more context. really can mean....1) actually,....2) unquestionably, .....3) very.... or 4) simply provide emphasis. Variation 1) is used more often in British English, while variation 2) is more common in American English. I have no idea why. ==== Here are some statistics from a study on adverb placement with the adverb "certainly". The numbers indicate how many times the expression appeared in a sample of 10 million words. ...............................BrE .................................. AmE has certainly.......... 22.................................. 13.4 certainly has ..........11.7.................................. 22.2 has probably ..........21.2...................................14.5 probably has ...........8.8 .................................. 18.6