Put the introduction in a function.
REPEAT
INPUT "Skip opening? (YES or NO)"; SKIP$
UNTIL SKIP$ =="YES" OR SKIP$ =="NO"
IF SKIP$ =="NO" THEN
SHOW_INTRO
ENDIF
'Code for the rest of the game goes here.
...
END
DEF SHOW_INTRO
'Code for the intro goes here
END
Functions are always better than GOTO and GOSUB.
1そうだね プレイ済み