U字开头的单词或词组
unzipuselessunfoldingundergoneusher inuntidyupunlikeunwillingunder the circumstancesunderestimateUUTunderneathunemployeduglifyunderwentutilizationunicornuniquenessuse upuncommonur-underlineunsupportedunavailableUTunhealthyurge sb to do sthupdatingurbanizationunrecognizedunpredictableunleashunbearableunderwearusageundouppercaseunawareunder the tableunfamiliarunusually
