DIM a$ : a$ = "Hello"

SELECT CASE UCASE$(a$)

CASE "GOODBYE"
  PRINT "GoodBye"

CASE "HEY"
  PRINT "hey what?"

CASE ELSE
  PRINT a$

END SELECT

SELECT CASE LCASE$(a$)

CASE "hello"
  PRINT "hi there!"

CASE "goodbye"
  PRINT "tootaloo"

END SELECT

Result:

Hello
hi there!