Arabien

What is actually the difference between the pronounciation of sin, dal, za and sad, dad, zay?

Klowj

I don't know between za and zay (I only know zay ز ) which is a normal z sound.

The difference between sin, dal and Sad, Dad is that the later are emphatics consonants. It's kinda hard to explain how to pronounce, but I think the area/surface of your tongue touching the palate is greater in the emphatics. For a non native, the sounds may be hard to distinguish, but with practice, you'll be able to do so.

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Rihla
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