uncover 揭開，揭露 ～ a dish of food
underestimate低估 ～ the difficulties of the task
undergo 經歷，遭受，忍受 ～ much suffering
underlie 位於之下 Many facts ～ my decision
undermine 在下挖 ～ a wall
undertake 著手做， 從事 ～ an attack
undesirable 不合意的，不受歡迎的 The drug has ～ side effects
uneasy 心神不寧的，不安寧的` be ～uneasy about the future
unfold 展開，開啟 ～ a newspaper
uniform 不變的，相同的，均勻，統一的 a ～ temperature
unify 使成一體，統一 become a unified nation
更新，使現代化 ～a textbook
upgrade 提高，使升級，改善 ～ products and services
uphold 舉起，高舉 He upheld his clenched hand
upright 挺直的，垂直的 an ～ seat
uproar 騷亂，騷動The public ～ over unclear-radiation hazards continues to mount
upset 弄翻，打翻 Ive ～ a tin of paint on the carpet
up-to-date 時新的，新式的，現代化的They are ～ on recent developments in the world computer industry
urge 推進，鼓勵 The president ,～d on by his staff, has decided to attend the talks
