Hello Alison, You will be able to listen to the right pronunciation on the following sites: http://www.howjsay.com/
 http://www.shiporsheep.com/ Sophie.

I understand what you mean- you're describing the 'softening' of consonants when they are short and next to vowels. FOr instance, Finnish does this: 'Mitta' is pronounced with a long and hard 't' sound. But 'Mita' the 't' is not only short, it becomes a 'd'. English does this when there are vowels on either side of a single consonant. For instance the 't' in 'autopilot' is about the same as the 'd' in 'radio'. But this is a factor mostly I think of the sound being pronounced very quickly- there isn't time for the longer stop of a final 't' as in 'brat'. Why not write 'd'? Because english isn't a phonetic language. Phonetic languages are usually those (like Finnish) which are spoken only for many centuries. Then a scholar comes along and writes it all down using some reasonable, consistent, alphabet. English, on the other hand, is a mongrel language made up of all sorts of different languages fused togtether- it's always been that way, it was a fusion of indigenous anglo-saxon dialects with roman latin as it was filtered through hundreds of different adaptations of romance languages, plus all the other words that have been added as america emerged as the 'melting pot' of the 19th century. Because all these different words were written and thenpronounced according to the rules of their home languages, the pronounciation isn't consistent. There's general trends to make words follow similar patterns, but plenty of times it's jsut what people actually say, regardless of what the academics say is 'correct'. It's easiest I think to think of English words existing as written words, and understand that each one has its own local quirks of pronunciation.

what dictionary are you using? normally, the correct pronounciation can be found in the dictionary

Hello Alison, these sites are also good for listening and pronunciation practice. http://www.elllo.org/ http://www.bbc.co.uk/worldservice/learningenglish/ http://news.bbc.co.uk/ http://www.usingenglish.com/
 http://www.englishpage.com/
 http://www.tolearnenglish.com/
 http://www.oup.com/elt/global/products/headway/
 http://www.flo-joe.co.uk/
 http://wordweb.info/free