U字開頭的單詞或詞組
user-definedultrasoundunnoticedunwindinguncutunequaluneasinessupsettingunscrambleunworthyunethicalunitingunmatchunder contractunyieldingUCunshiftunderpinunspecifiedunisexultrasonicupchuckUARTuniversal languageunsteadyUnicodeunmannedunifyinguntamedULFunawarenessunpaidunqualifiedunseenultramarineUnion Jackunderpantsunbiasedurge tousurpunparalleledunconcerned