
MATHEMATICA

lst = {zero, one, two, three, four, five, six, seven, eight, nine, ten, eleven, twelve, thirteen, fourteen, fifteen, sixteen, seventeen, eighteen, nineteen, twenty, twentyone, twentytwo, twentythree, twentyfour, twentyfive, twentysix, twentyseven, twentyeight, twentynine, thirty, thirtyone, thirtytwo, thirtythree, thirtyfour, thirtyfive, thirtysix, thirtyseven, thirtyeight, thirtynine, forty, fortyone, fortytwo, fortythree, fortyfour, fortyfive, fortysix, fortyseven, fortyeight, fortynine, fifty};
f[l_] := StringReplace[ ToString@l, {"a" > "2", "b" > "2", "c" > "2", "d" > "3", "e" > "3", "f" > "3", "g" > "4", "h" > "4", "i" > "4", "j" > "5", "k" > "5", "l" > "5", "m" > "6", "n" > "6", "o" > "6", "p" > "7", "q" > "7", "r" > "7", "s" > "7", "t" > "8", "u" > "8", "v" > "8", "w" > "9", "x" > "9", "y" > "9", "z" > "9"}]; f@# & /@ lst
