U字母开头的单词或词组(第6页)：

• unwelcome
• uncommon
• UFO
• ungrateful
• unhelpful
• usually
• USA
• unleaded
• unpainted
• um
• unaware
• unimportant
• unable
• unforgettable
• unhappy
• unload
• up to
• unpleasant
• university
• unexplored
• uninteresting
• unnecessary
• unkind
• untidy
• used to
• upstairs
• unhealthy
• umbrella
• uncle
• under
• undergo
• undergraduate
• underground
• undertake
• underline
• underneath
• understand
• unemployment
• unfair
• understanding
• unfortunate
• union
• unit
• unite