你知道辅音 t 是如何变音的吗？

billzhao

The Flap

A flap occurs in three situations.
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  1. A flap occurs when a 't' comes between two vowels. The pronunciation of the 't' in these incidences sounds
      like a 'd' and is said very quickly.
8 g* {3 r7 n7 J3 T( P" y                                     
        Listen to these sound changes. The first word is with proper enunciation, the second word is with the sound changes. Then the word is used in a sentence.
                                    
/ x0 ~/ ]+ |8 i6 _( W8 t9 u- Y4 S                 
  water becomes wader
! ?1 S; a, p) B) c6 A  Do you need some water?
; ^6 \1 Z& c; V' z3 U                 
  letter becomes ledder
  The letter was in the mailbox.
                
1 S1 O! U0 C: e  bottle becomes boddle
# U8 a! f2 ^" D& Q% i  c/ ^6 t  The bottle broke when it hit the floor.
& N+ a) x& F3 o! u1 F; T" V3 X' p, {                 
  butter becomes budder
  The butter melted in the sun.
                                    
  2. Flaps also occur when a 'd' comes between two vowels. The 'd' is still pronounced with a d sound, but it is
5 X5 H# |; F* H& J1 W, i      said very quickly. In the normal pronunciation of the d sound the tip of the tongue is placed on the tooth
7 `$ O: t4 O' d      ridge (the area where the top front teeth meet the top of the mouth) before the expiration of air to produce
      the sound. With a flap, the tip of the tongue barely touches the tooth ridge and the 'd' sound is made very
$ y8 V4 c' U1 ?5 @      quickly.   
                                    
        Listen to these sound changes. The first word is with proper enunciation, the second word is with the sound changes. Then the word is used in a sentence.
' `  O( f& f# b- n: Z$ o  p) |/ o                                     
                   medical        She is a medical student.
                   sediment            
The sediment on the river bottom is course sand.

# ~& j8 ~; X# t  z( b9 j9 o8 n) Q9 `0 g                    cadence           
Drums keep the cadence in a marching band.
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                   cider         This apple cider is great.
0 ^+ U0 }& Z0 }& P, B* W                    spider        A spider has eight legs.
' U1 \' i4 ~2 Q+ E& r                                     
+ }, ?/ b# C3 L6 ?8 ^  3. The third flap occurs when with linking of the consonant final letter of one word and the vowel letter of the
       next. (see section on linking)
                  
; Q0 Q0 v" T* e         Listen to these sound changes. The first phrase is with proper enunciation, the second phrase is with the sound changes. Then the word is used in a sentence.
/ T6 C; t* A) S& ]( g! r) ^                   
           'right away'  becomes righ(d) da  way
- E6 x9 V, C7 Z6 n" V/ J& A          I'll get your bags right away sir.

( L( B: p# Z3 p$ m7 |$ x7 d
                  
           'what if' becomes whad dif
          What if we go to Paris for vacation?
  R' g' p2 O7 b) _' h

, T) O" {( L6 T                   
9 z; y6 b4 C$ F/ r, F             'might I' becomes migh(d) di         
6 j( \, b) ?* ^- V- V           Might I suggest a new tie?
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4 L$ ]8 B; M& Y+ f. qNote: The flap does not occur in some words (what, that) if they are spoken alone, without other words to
, }# k+ Y; ~- J) D$ Q          link to.

billzhao

The Glottal Stop
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When a 't' is followed by a vowel + n syllable  (eaten), the 't' sound is replace with a glottal stop, which is a complete closing of the vocal cords for a short moment. A glottal stop sound can be heard in the pronunciation of the negative uh uh.
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. l; |+ {. q, e2 @' W- k6 u                            
        Listen to these sound changes. The first word is with proper enunciation, the second word is with the sound changes. Then the word is used in a sentence.
                           
0 `5 {; O/ \4 x. i" h4 ]) [2 E1 x& O        
    'eaten' becomes ea'n  
   Have you eaten yet?
       
    'satin' becomes sa'n  
   Satin sheets are nice to sleep on.
       
8 R- Z" V  j% d2 c; ~7 s$ E    'sentence' becomes se'ence
   This sentence makes no sense.
       
' s- ^$ h9 m2 B0 V, R    'mountian' becomes moun'n   
. V. P6 O6 B1 q, ^7 I' @/ m' \   I'm not much of a mountain climber.
       
    'getting' become ge'n        
   I'm getting to old for this.
       
    'button' becomes but'n   
   Sam lost a button on his shirt.

billzhao

Can and Can't
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6 m9 f; B6 D3 i) y  K3 W, ^
# c# A3 T, a" P# w5 Z$ EIn an affirmative 'can', the can is pronounced as 'kn'. The modal verb 'can' in the sentence is unstressed; the main verb is stressed.
                                             
+ B* p8 _* ]* Z8 t6 f0 M/ H8 o- c   Listen to these sound changes. The first phrase is with proper enunciation, the second phrase is with the sound changes.
   Then the word is used in a sentence.
                                             
       
   'We can swim' becomes we kn swim  
) g0 F# Y8 ?" d6 Z# ~0 i5 m   We can swim in the lake.
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   'I can cook' becomes I kn cook.
   I can cook pizza.

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2 B9 v8 y8 K2 \& H        
6 @2 v  v% O& L6 ^. i# P   'She can read' becomes she kn read  
/ l* D  A# U0 U7 K8 B2 C   She can read Italian and Russian.
: t1 c5 c! m, p' }) D

8 C  ?3 T- G& g6 M0 c        
   'They can ride' becomes they kn ride.
9 M; {( `( J1 g6 q% U5 c+ x   They can ride on the roller coaster.
/ S6 S/ e% [+ N( o3 q: h
                                             
In the negative, both the modal (can't) and the main verb are stressed. However the 't' in can't is dropped and replaced with a glottal stop if the next sound is a consonant.
                                             
1 Q9 a- f/ j3 M# Q! ?3 Y1 G, Y   Listen to these sound changes. The first sentence is with can, the second with can't. Note that both the modal and main
   verbs are stressed in the negative sentence.
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* ^- f- c; e% |& n/ ^) l) |$ ~/ |        
: G8 ^' l  x& t, N6 z  'We can't go' becomes
   We KAN' GO.  

* Y1 u& [/ Z% Z$ A) k5 IWe can go to the movies.
We can't go to the movies.

       
. q) a( M  _- T' F3 p, z: [  'Larry can't speak' becomes
   Larry KAN' SPEAK.

Larry can speak French.
Larry can't speak French.
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: i8 g9 _( ~' [0 ?" X! c/ T        
  'She can't do it' becomes
5 X. h8 k5 n* R   She KAN' DO it   

2 t3 G* R+ F' a9 oShe can do it.
( `) N1 Q% I8 d  v" xShe can't do it.
9 Q. o. T$ O! S/ f; I
       
  'Some people can't sing' becomes
& D; a7 T$ V# l   Some people KAN' SING
Some people can sing.
Some people can't sing.
+ M  T* D+ G5 i+ F+ f. @3 `
                                             
If the next sound after 'can't' is a vowel, a flap occurs as in 'She can't  ignore it'. (... can't  tig-nore...)
                                             
   Listen to these sound changes. The first phrase is with proper enunciation, the second phrase is with the sound changes.
3 G1 z& A$ ~  q1 a' |   Then the word is used in a sentence.
6 A5 b% b: k- H5 J7 P0 C. P* `# n( Z                                              
+ t3 d! e4 m/ p# V5 m        
  g3 b* @& g3 E   'can't attend' becomes can't  attend. (... cand da-ttend)
   We can't attend the concert.
       
- P0 v3 Z# P$ W. }) z4 ]   'can't invite' becomes can't  invite  (... cand din-vite...)
. j! s; t8 }1 r/ l1 [" Y   Wally can't invite her to the party.
9 p3 r* C% U" x6 n# G: M' r0 g        
  I, c# N, c$ `   'can't answer'  becomes can't  answer (.. .cand dan-swer)
   He can't answer the question.

: ]) E7 J4 ]/ T. n        
) M6 P2 {/ \/ v+ d! S6 s   'can't understand' becomes can't  understand (... cand dun-der-stand.. )
   I can't understand what you are saying.

billzhao

Negative Contractions

Many times a native speaker does not pronounce the final 't' in a negative contraction (can not= can't, do not =don't, have not= haven't). The pronunciation is replaced by a glottal stop. (see above)

0 b1 d# t+ z+ X                   
     Listen to these sound changes. The first phrase is with proper enunciation, the second phrase is with the sound
4 O2 l8 N. {& _- k7 V     changes. Then the word is used in a sentence.
) y+ O/ O/ f7 B; Y  {7 Y                           
       
' M. Q6 X8 c  [    'wouldn't'  becomes wouldn'      
$ Z: R) {/ S9 ^5 O  R1 [2 S   Why wouldn't you go to the dance with me?
       
" D" n# b9 w& [7 @* `+ z6 h' g# R8 g   
5 d- c9 n) q8 T$ y0 W8 O, N
       
: G% N& ?6 V! X1 }4 x    'couldn't' becomes couldn'
. b# V, }! b. t- `  a- K3 N7 l. }    I couldn't do it because I was sick.
       
% n; V- a" Y( [) ?3 p# L   

       
    'shouldn't' becomes should'n         
   He shouldn't have eaten the apple.
6 w- c4 I& h7 {8 |, C1 c5 g4 ]        
   
( x5 _, z; N; l9 ?
       
    'doesn't' becomes doesn'
; S: W0 W$ K: X% j- b   Larry doesn't study hard enough.
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