Test word fydyw : if y=t, d=e → f t e t w → ? "f t e t w" — maybe "state"? s→f? No. "treat"? t→f? No.
afdl = "from": f→a: shift –5 (or +21) r→f: shift –12 o→d: shift –11 m→l: shift –1 — inconsistent. afdl brnamj drdsht fydyw shwayy
Try afdl = "with": w→a: +4? No, w=22, a=0: difference +4 mod 26? 22+4=26=0 yes. i→f: i=8, f=5: –3 mod 26 — not same shift. So not Vigenère with fixed key length 1. Reverse each word: afdl → lfda brnamj → jmanrb drdsht → thsdrd fydyw → wydyf shwayy → yyawhs Result: not English. Test word fydyw : if y=t, d=e → f t e t w →