unanimous 全体一致的，一致同意的
undertake 着手做， 从事 ～ an attack
undesirable 不合意的，不受欢迎的
uneasy 心神不宁的，不安宁的
virtue 美德，德行 Among her many ～s are loyalty ,courage, and truthfulness
substitute 代替者，代替物 He is the doctor’s ～ during holidays times
subtle 微妙的，巧妙的 His whole attitude has undergone a ～ change
subtract 减，减去 Subtract 4 from 10 you get 6
succession 连续，一系列 a ～ of debates
suck 吸，A large mosquito was sucking blood from the back of her hand
vital 有生命力的 The heart is a ～ organ
void 空的 a ～ space
wedge 楔子，三角木 Please put a ～ in the door so that it will stay open
diffuse 四散开；漫射
yield 生产，产生，带来 This orchard ～s apples and pears.
zeal 热心，热忱，热情 a man of ～
zigzag之字形的，弯曲的 a ～ road
wander 漫步，徘徊 He ～ed home
ward 病房 a 4-bed ～
