are there any other consonants that function as vowels like the letter Y??

Answer 1

actually there are only 5 vowels...a,e,i,o,u but y and w are also considered vowels.for example when 'the' comes before a word starting with a vowel...it is pronounced 'thee' and sometimes even before year and other words starting with y.although this is considered incorrect by some people

Answer 2

W which is literally derived from a "double U"

Example: the word CWM (pronounced "coom")
which means a low valley.

Here, W is clearly used as a vowel to make the UU sound
as in "vacUUm"

Answer 3

no