Anyone who ever sang along to that song has flubbed the lyrics at one time or another.
That is kind of funny but largely true.
Funny, never happened to me with the National Anthem or the Pledge of Allegiance which are certainly more complicated.
But then, after all these years, I could still recite the Scout Oath.
Heh, I tried to remember the USN General Orders of a Sentry, but those escaped me utterly! (I can still remember how to do the 16 count manual of arms, though. Isn’t that odd? I would think that would get jettisoned as useless knowledge a long time ago!