[s] [ʃ] [tʃ]

sea/sheet/chicken
Exercise One: Word Conparison
Listen to the following words from your tape and repeat.
sip ship sane shane watched washed
lass lash least leashed chin
shin cheap sheep matching mashing
Exercise Two: Tongue Twisters:
She sells seashells by the seashore.
The shells she sells are surely seashells.
So if she sells shells on the seashore, I'm sure she sells seashore shells.