If you want to sound like an American speaker, you should learn rules of American English pronunciation. There is a lot of them but learning at least some basic rules will dramatically improve your accent. What are these rules?
Note: some of the rules listed below are not only used in American English. Many foreign speakers make mistakes when it comes to standard English rules so I decided to include these rules too.
"T" becomes "D"
"T" becomes "D" when it falls between two vowels.
For example: "bitter" is pronounced like "bidder". "Water" is pronounced like "wader".
Of
Even though the word "of" is spelled with "F", it's pronounced with "V". It's an exception.
For example: "it's made of wood" is pronounced "it's made ov wood".
"S" or "Z"
If a word ends with a voiceless sound (F, K, P, T, except for "S"), "S" is pronounced like voiceless "S", but when it ends with ch, dg, s, sh, z, a vowel or a voiced consonant, it's pronounced like longer, voiced "z" ("zzz").
For example: "He looks" is pronounced with voiceless "s" (it ends with a "K") but "judges" is pronounced with voiced "z" - like "judgezzz". "Tree" ends with a vowel, so it's pronounced "treezzz".
-ed endings
Many verbs that are in the past tense end in "-ed" but "-ed" is pronounced differently, depending on the word ending. If a word ends with a voiceless consonant, "-ed" is pronounced like "T". If a word ends with a voiced consonant, it's pronounced like "D". If a word ends with "T" or "D", "-ed" is pronounced like normal "ed".
For example: "I walked" is pronounced "I walk-t" (because it ends with "K"), "I moved" is pronounced "I mov-d" (because it ends with a voiced consonant). "I voted" is pronounced "I voted" because it ends with "T".
-ng endings
There are three nasal sounds in English and "ng" is one of them. "Ng" is a combination of "N" and "G" but "G" is not pronounced.
For example: "he is walking" is pronounced like "he is walkin". "G" is not pronounced!
These are some basic rules of English and American English pronunciation. There's a lot more rules of pronunciation but learning and practicing the above five will unquestionably improve your accent.
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