How do you learn to play fretless string instruments?

Question by Costescu: How do you learn to play fretless string instruments?
How do you learn to play the violin, chello, and so on.. ?
I’m not intending to learn to play these instruments, i’m learning to play the guitar using online lessons.
But the violin has no frets to indicate where you should press the string with the finger to make the right note. How is it possible to learn to play these instruments? I’m very curious

Best answer:

Answer by df74sg
beginner violin will have white “frets” or fingerings to guide the player. After some time, the player will be able to play without the “frets”.

http://www.fretlessfingerguides.com/how_to_use_it.html

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