simple

absolute arcadian austere barest bare benighted blockheaded careless chaste childlike classic clean clean clear cleanest cleanest clearer clearest common commonest credulous crude crudest daft daftest dense denser dimwitted doltish dopey doting downright down to earth dry dull duller dupable earthy easy as pie easiest easier easy effortless elegant facile fatuous featherbrained familiar feeble-minded foolish forthright gullible guileless harmless homey homely humblest humblest humble humble homelike homespun imbecilic imbecile ignoble ingenuous innocent literal loopy low lowly main mere mindless modest modest more elegant more familiar more modest more modest more natural more primary more primary more readable more understandable more virginal most primary most primary most virginal naive naked natural nominal nothing to it nothing to it oafish open-and-shut open and shut/open-and-shut ordinary oversimplified pastoral pellucid perfect plain plain primary primary/prime primitive primest pure purest readable rude rudimentary rural rustic rustic self-effacing senseless shallow shallower sheer silly simple-minded single slowest slow slower softheaded soft soft softer softer spartan spontaneous stark stupid thick-witted tomfool unaffected unassuming uncomplicated understandable undiluted unimposing unintelligent unmitigated unostentatious unoffensive unqualified unprocessed unpretentious unsuspecting unvarnished unwashed unworldly user-friendly very virginal voluminous