Pangram checker

You are encouraged to solve this task according to the task description, using any language you may know.
A pangram is a sentence that contains all the letters of the English alphabet at least once.

For example:   The quick brown fox jumps over the lazy dog.



Task

Write a function or method to check a sentence to see if it is a   pangram   (or not)   and show its use.



Related tasks

   determine if a string has all the same characters
   determine if a string has all unique characters


PangramBrokenAt("This is a Pangram.") ! => 2 (b is missing)
PangramBrokenAt("The quick Brown Fox jumps over the Lazy Dog") ! => 0 (OK)
 
FUNCTION PangramBrokenAt(string)
   CHARACTER string, Alfabet="abcdefghijklmnopqrstuvwxyz"
   PangramBrokenAt = INDEX(Alfabet, string, 64)
   ! option 64: verify = 1st letter of string not in Alfabet
END