if we ask a question like "if a number is divisible by 2"
then there are two answer possible either "yes" or "no".
like take a number 8
if 8 is divisible by 2?
ans is yes
if we take a number 9, then answer will be "no"
So, where yes and no both ans possible, that language is called turing decidable language. Because we can definitely say yes and no ans for it
In turing recognizable language Similarly we can predict "yes" ans, but cannot say anything about "no" ans