Two of my favorites:
1) FDR after Pearl harbor quoted as “Yesterday December 7th, 1941 a DAY that will live in infamy…”
What he actually said was “…a DATE that will live in infamy…”
his speach in both audio and his typed copy are available online to see/hear. I have even seen it mis-quoted in some books.
(as an aside a day living onin infamy doesn’t make sense as the day is gone. However what he was saying is the DATE DECEMBER 7th 1941, will live on in infamy, and he was right as it certainly does)
2) Neil Armstrong on the moon “That’s one small step for man, one giant leap for mankind” This quote as heard on the recording and often repeated is nonsense as MAN and MANKIND are essentially synonyms. What he meant to say (and insists he did say, and to be fair the audio isnt clear) was “Thats one small step for A man (i.e. him) one giant leap for mankind.” (as should be obvious “A man” is not a synonym to “Mankind”)