Corrections Marked

I'm learning English., but The the truth is, that I'm not doing enjoying it with pleasure. Of course, if you think I hate English, I have to say really must explain, this that is not the case. I love English, but I don't think I will learn it when until pigs fly. :) I'm so tired of trying so much hard to learn it, and not succeed making any progress. I think if the English intonation and pronunciation of English were a bit easier, I would have mastered English the language by now. I have no don't have any problems understanding its grammar, it does not bother me, but I feel that I don't make any progress haven't succeeded in learning its intonation properly. 

I am one of those people who either learn learns something well, or learn it not at all.

Sorry, I can't write anymore any more, it is vital for me now I need to see an a dentist as soon as possible! ;)

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Corrected

I'm learning English, but the truth is, I'm not enjoying it. Of course, if you think I hate English, I have really must explain, that is not the case. I love English, but I don't think I will learn it until pigs fly. :) I'm so tired of trying so hard to learn it, and not making any progress. I think if English intonation and pronunciation were a bit easier, I would have mastered the language by now. I don't have any problems understanding grammar, it does not bother me, but I haven't succeeded in learning intonation properly.

I am one of those people who either learns something well, or not at all.

Sorry, I can't write any more,I need to see a dentist as soon as possible! ;)

Remember that if a word begins with a vowel sound (not necessarily a vowel, remember "hour" actually sounds like "our"), then we use the indefinite article "an", and if it starts with a consonant sound, then we just use "a"... therefore, we see "a dentist", not "an dentist".

You might find the English "th" sound particularly difficult to pronounce, but remember, almost every language learner has to learn a few different sounds to get their pronounciation correct in their target language! I know a lot of people have trouble with the "x" sound in Mandarin, and the "r" sound in German, the only reason I don't, is because I believe in myself... if you stop putting yourself down and saying that you can't do something, you'll never be able to do it!

Your English is actually much better than you seem to think it is, there are a few mistakes, and although it may not sound entirely natural, I could understand exactly what you were trying to say- you didn't make any spelling errors!. I believe in you, believe in yourself and you'll go far!