For all of you people who are completely stumped on how "TWENTY QUESTIONS" figures out whether to say "Yes" or "No," look at line 310. You will notice that it is looking at the last character in your inputted question and only the last character! What it is looking for is a vowel, if it finds one then the answer is "YES"; however, if it does not find a vowel the answer is "NO."
Another thing, on the Apple when you attempt to enter line number 350 you will get the following:
350 IF NOT HEN PRINT "NO"
to fix this problem you will have to enter:
350 IF NO = 1 THEN PRINT "NO"
you may wish to do this for YES (the variable) also.
One other thing, you might wish to change line number 340 to read as follows:
340 IF YES = 1 THEN PRINT "YES" : GOTO 390