2. very useful 宝贵的,有价值的

valuably adv.

value n; invaluable adj. 千金难买的。

ant. valueless 毫无价值的。

value ['v lju:] n. 1. the degree of usefulness of something 重要性，用途，益处

2. to act together for a purpose (为一定目的而)联合行动，一致行动

united adj. 1 joined in a state of love, agreement, etc. 团结的，和睦的

2 with everyone concerned having the same aim 一致的，统一的

3 (cap. In names) (作名称时

大写) joined in a political organization结合于一个政治组织内的

universe n. (often cap.) (常大写) all space and the matter which exists in it 宇宙；世界；天地万物

unknown n.& adj. (a person or thing) whose name, value, or origin is not known(人或事物的名称、价值或起源)未知的，未被发现的，不了解的；未知的人(或事物)

university n. 大学

unless conj. if not; except if 如果不；除非

unpleasant adj. not pleasant; causing dislike; not enjoyable; unkind 使人不愉快的；讨厌的；不合意的；不和善的

-unpleasantly adv.. -unpleasantness n.

unreserved adj. without limits or reservations 无限制的，无保留的；充分的；坦白的

unrest n. 不安；骚动

unsold adj. 未销售的

unsuccessful adj. 不成功的；失败的

until also till(亦作till)- prep.& conj. up to the time when, up to as late as 直到…为止;在…以前

not…until… 直到．．．．．．之前；不到．．．．．．(不)

unusual adj. not usual; rare; not common; interesting because different from others 不平常的；罕见的；与众不同的；独特的

up adv. 1 from below towards a higher place; away from the floor, the ground, or the bottom 向上；向更高处；离开楼面(地面，底部)

2 in a high place 在上；在高处

3 into an upright or raised position 趋向直立或竖起姿势

adj. 1 directed or going up 向上的

2 (of a road )being repaired (道路)正在修理的

prep. 1 to or in a higher place in; upwards by way of 向．．．面; ;在．．．上面；由．．．向 上

2 along; to or at the far end of 沿着；向．．．的远端；在．．．的远端

3 against the direction of(the current of a river) 逆着(河流)的方向 (＜反＞down)

4 up and down:

a. higher and lower on 沿．．．上(去)下(来)

b. backwards and forwards along 沿．．．来 回

upon prep. 在．．．．．．上面

upstairs adv.& adj. at, to, or on the upper floor(s) of a building 在楼上(的)；往楼上(的)

upwards also upward AmE(亦作upward <美>)- adv.

1 going up 向上，上升

2 with a particular side facing up (某一面)朝上地

uranium n. a heavy white metal that is a simple substance(element)

and gives out radioactivity 铀(放射性元素)

us pron. (object form of WE) (WE的宾格)

use n. 1 the act of using or state of being used 用；使用；应用；利用

2 the ability or right to use something 运用能力；使用权

3 the purpose or reason for using something 使用目的；用途；用处

4 the usefulness or advantage given by something 效用；好处；价值

use v. used, using 1 to employ for a purpose; put to use 用；使用；利用；应 用

2to finish; consume 消费；消耗；耗尽

3 derog (贬)to treat (someone) with consideration only for one’s own advantage(为私人利益)利用(他人)；自私地对待(某人)

v. used, BrE negative short forms usedn’t, usen’t (<英>否定缩略形式 usedn’t, usen’t )

(used in the past tense only, to show that something happened always or regularly)(仅用于过去式中，表示某事过去经常或有规律地发生)

make use of 利用；借用

use one’s head 动脑筋；仔细考虑

USAGE 1 Used to and would are both used of things that happened always or regularly in the past, but would is not used at the beginning of a story用法: Used to和would 都用以表

示事物过去经常或有规律地发生，但在开始叙述时不用would: We used to swim ev.ery day

When we were children. We would run down to the lake and jump in… 我们小时候天天去游泳。我们常跑到湖边，跳进水里．．．

2 The usual question form of used to is Did(n’t)

sl: use/used to, but Used/Usen’t she to are also possible. used to 的常用疑问形式是

Did(n’t)she use/used to, 但也可用Used/Usen’t she to. in the NEGATIVE, She used not to/usen’t to and She didn’t used/use to are all possible, but She never used to, which expresses the same idea, is probably more common. 在否定句中，She used not to/usen’t to 和She didn’t used/use to 两者都可用，但意思相同的She never used to 也许用得更为普遍

used 动词use的过去式

used to 过去常常

be used to 习惯于

useful adj. 1 effective in use 有用的；有效的；有益的 2 helpful 有帮助的

useless adj. not of any use 无用的；无效的；无益的

–uselessly adv.

–uselessness n.

usual adj. happening most often; customary 通常的，平常的，惯常的

as usual as generally has happened before 象往常一样；照例

usually adv. often; generally 通常，经常，惯常

　V

vacation [v 'kei n] n. A time of rest, amusement, and recreation away from one's job or school Am. E 假期，休假

syn. holiday Am. E 可指传统节日，也可泛指休息日，常用复数表示长时间休息

leave 因事，因病请假

valley ['v li] n. The land lying between two lines of hills or mountains 山谷，河谷

various [v' ri s] adj. different; several, number of 各种各样的，不一样的

variously, variety, vary

ant. different 不同的，不一样的

valuable ['v ljuble] adj. 1. worth a lot of money 贵重的，值钱的

3. a piece of furniture, storage apparatus, etc., which can be fitted with others of the same type 一套用具(如家具、贮藏用具等)

unite v. 1. to join together into one (使)联合；(使)团结；(使)合并

2. an amount or quantity taken as a standard of measurement (作为计数或计量标准的)单位

3. a club or society, esp. a TRADE UNION 协会；联合会；(尤指)工会

unit n. 1. a thing or group regarded as being a complete whole 单位；单元(指被视作一个整体的事物或团体)

2. (often cap.) (常大写) a group of countries or states joined together 联邦；联盟

3. unnatural 非自然的；反常的；怪异的

uniform n. a certain type of clothing which all members of a group wear, esp. in the army, a school, or the police(尤指军人，学生，或警察的)制服

union n. 1. the act of joining or state of being joined into one 联合；合并；结合

2. not likely to give good health 对健康不利的；对身心有害的

2. to make or become clear, more fully known, etc. 显露，表露

unhealthy adj. 1. not generally in good health 不健康的；有病的

3. fml or polite(正式；雅) to have been informed; have found out(a fact) 获悉；得知；发觉

understanding n. the act of understanding; power to judge 理解，了解，领会；理解力，判断力

underwater adj.& adv. (used, done, etc.) below the surface of the water 在水下的，在水中(使用，进行)的；在水下，在水中(使用，进行)

undivided adj. complete 完整的，未分割的；专一的

unfair adj. 不公平的;不公正的

unfold v. 1. to open from a folded position 展开，摊开，打开