fort

n.要塞；城堡

formed, former, formerly, formic acid, Formica, formidable, formidably, formless, formlessly, formula, formulaic, formulate, formulation, fornicate, fornication, forsake, forsaken, forseeable, forswear, forsythia, forte, forth, forthcoming, forthright, forthwith, fortieth, fortification, fortified wine, fortify, fortissimo, fortitude, fortnight, fortnightly, FORTRAN (also Fortran), fortress, fortuitous, fortuity, fortunate, fortunately, fortune,