U字開頭的單詞或詞組
uplinkunopenedunsortedungrudgingupriseunder heavenunsealup a gum treeunder the influence ofup to scratchuntangleumpteenUdmhunconstitutionalunder licenseuniversalizeunaccompaniedunboundedunmanageableunoccupiedunconcernunadornedunerringunclenchuplandunitary systemup to thenunjust enrichmentunit celluntimelyumberunbentusuryunlicenseduncoupleultraviolet rayunguardedunexaminedup to the minuteurinary systemunfrozenunknown parameter