It could be simpler than you probably expect.
Remember the following, and, FOR THE TIME BEING, forget everything else you have learned about the US accent. Do not overload yourself!!
1. Americans "over yod-drop" i.e. Anticipate that they would probably punch in a "y" as well as a curve with every vowel sound. For example, "and" might [just might] become YEAND. Now, even in global/British English, our simple Indian vowels hardly exist. For example, Coat is actually K+"Y"+O+U+T. Americans do more of this than anyone else.
2. Americans join up words all the time. For example, HOW TO may [just may] become HAHDDA. Now, if I give you the rules for their "T" sounds, and if I say "T at the beginning of a word or anywhere else in a stressed syllable remains a sharp, popping T sound," how would you apply that rule to the T in "HOW TO"?
You see, T was at the beginning of the word - "to", but in the middle of the staircase - Hahdda. That's why it became HAHDDA instead of HAHTTA because rule-2 of T sounds is T in the middle or in an unstressed syllable becomes a soft D sound. Okay, now what on earth is this stressed/unstressed business?
You can stress and unstress syllables in many ways, but I mean doing so by elongation vs. shortening. So, PHOTOGRAPHY remains photography - sharp, popping T sound despite T being in the middle. But PHOTOGRAPH becomes "pho-duh-graph".
3. The other T rules are T immediately following N is silent. For example, intercontinental is INNERCAHNNINENNAL. Many exceptions to this. Notably - INTEREST remains interest, not innerest. T at the end (of staircase - as you've now got the concept) is a HELD SOUND. Now, that's difficult for you to do. Just try to understand it. Okay, forget rule-5 for now. This is already an overdose.
4. No, Americans are not from Bihar and U.P. They are not offering you PAPCORN instead of popcorn. Here's what they're doing: Suppose you proceed to form a normal AW sound as in the word WATER. THEN, HALF-WAY THROUGH IT, YOU SUDDENLY LET YOUR JAW RELAX AND DROP A BIT. No, do not try doing it. Understand that this is what they are doing. So you'll anticipate it, be ready, and grasp it the moment it happens.
Enough for now. My misspellings are because I'm being harried to log off this PC and go. Sorry.
Just time to upload a few pages on myself. Call 9891727324 / email blessedheights@gmail.com
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