U字开头的单词或词组
uneducatedunfavorableupdate nowunpretentiousundefined variableunisexuncannyunfavourableunwantedunconcernedunsettledunbalancedUCLunavoidableuninhibitedunbalanceunknowinglyuntamedundercutUNIXunder one's belturic acidUruguayundertakerunreflectinguserinfoU.S.S.R.unambiguousunconditionalupwardunkindunregisteredunnamedunfathomableunofficialundertookundisturbedupturnunresolvedutility functionunbiasedurethane
