C2 adjective /ʌnˈsʌlid/

unsullied

无暇

Meaning

not spoiled or made impure; perfectly clean or pure

Example

His reputation remained unsullied despite the accusations.

尽管有指控，他的声誉仍然无暇。

B1 adjective /ˈjuːnɪfɔːrm/

Uniform

制服

Meaning

consistent; identical; standardized

Example

All students must wear a uniform to school.

所有学生必须穿制服上学。

B1 adjective /ʌnˈplɛz.ənt/

Unpleasant

令人不悦的

Meaning

not giving or causing pleasure; disagreeable

Example

The medicine had an unpleasant taste.

药物有一种令人不悦的味道。

C1 verb /ʌnˈrævəl/

unravel

Meaning

To undo twisted or knitted threads; to solve or explain something complicated.

Example

The detective worked hard to unravel the mystery.

C2 adjective /juːˈʒʊəriəs/

usurious

高利贷的

Meaning

Charging excessively high interest rates on loans.

Example

The bank was accused of offering loans at usurious rates.

该银行被指控以高利贷利率提供贷款。

C2 adjective /juːˈbɪkwɪtəs/

ubiquitious

无处不在

Meaning

Present, appearing, or found everywhere.

Example

Smartphones have become ubiquitous in modern society.

智能手机已经在现代社会中无处不在。

B1 preposition, adverb, adjective /ˌʌndərˈniːθ/

underneath

在……下面

Meaning

Located directly below or beneath something

Example

The keys were hidden underneath the pile of papers.

钥匙被隐藏在那堆文件下面。

C2 verb /ʌnˈfrɒk/

unfrock

剥夺神职

Meaning

To remove a priest from his position or deprive someone of a rank.

Example

The corrupt priest was unfrocked after the investigation.

腐败的牧师在调查后被解除职务。

A2 noun /ˈjuːzər/

user

用户

Meaning

a person who uses or operates something

Example

He is a frequent user of this app.

他是这个应用程序的常用用户。

C1 adjective /ˌjuːtɪlɪˈtɛəriən/

utilitarian

Meaning

Designed to be useful or practical rather than attractive; relating to the doctrine that actions are right if they are useful or for the benefit of a majority.

Example

The building had a simple utilitarian design.

C1 adjective ʌnɪnˈhæbɪtəbəl

uninhabitable

不可居住

Meaning

Not suitable or safe for people to live in.

Example

Rapid urbanization can make cities uninhabitable.

快速城市化可能使城市变得无法居住。

A1 preposition/conjunction /ʌnˈtɪl/

until

直到

Meaning

up to the time of

Example

I will wait until you come back.

我会等到你回来。

B1 adjective /ˌʌnɪmˈpɔːrtənt/

unimportant

不重要的

Meaning

not having much value, significance, or influence

Example

The detail seemed unimportant compared to the main issue.

与主要问题相比，这个细节显得不重要。

B2 verb /ʌpˈhoʊld/

uphold

维护

Meaning

to maintain or support a principle, law, or decision

Example

The judge promised to uphold justice at all costs.

法官承诺不惜一切代价维护正义。

C1 adjective /ʌnˈtʃælɪndʒd/

Unchallenged

无可争议的; 被接受的没有反对; 没有对手

Meaning

not disputed or questioned; accepted without opposition; having no rival

Example

He remained the unchallenged champion for five years.

他五年保持不败的冠军。

B1 verb /ʌnˈlɒk/

unlock

解锁

Meaning

to open something that is locked; to make something accessible or available

Example

She used the key to unlock the door.

她用钥匙解锁了门。

C2 adjective /ʌnəˈpiːzd/

unappeased

不平息的

Meaning

Not satisfied or calmed; still feeling discontent or anger

Example

Despite the apology, she remained unappeased.

尽管道歉，她仍然不平息的。

C2 noun/verb /ˈʌpˌkæst/

upcast

向上投掷

Meaning

Verb: To cast or throw upward. Noun: Something thrown or directed upward.

Example

The fisherman upcast his net into the air.

渔夫把他的网投向空中。

B2 adjective /ʌnˈfeɪ.vər.ə.bəl/

Unfavourable

不利的; 逆境的

Meaning

not helpful or advantageous; adverse

Example

The weather conditions were unfavourable for our outdoor event.

恶劣的天气条件不利于我们的户外活动。

B2 adjective /ˌʌn.əkˈsep.tə.bəl/

Unacceptable

不可接受

Meaning

not satisfactory or allowable; not acceptable

Example

The quality of work was completely unacceptable.

工作质量完全不可接受。

C1 adjective /ʌnˈskeɪðd/

unscathed

毫发无损

Meaning

Without suffering any injury, damage, or harm.

Example

She escaped from the accident unscathed.

她毫发无损地逃离了事故。

B2 verb /ˌʌndərˈɡoʊ/

undergo

经历

Meaning

to go through something, especially something unpleasant or difficult

Example

She had to undergo surgery to recover.

她不得不接受手术以恢复。

C1 adjective /ʌnˈsoʊld/

unsold

未售出的

Meaning

not sold; remaining without a buyer

Example

The unsold goods were returned to the warehouse.

未售出的商品被退回仓库。

B2 adverb /ʌnˈkaɪndli/

unkindly

残忍地

Meaning

in a cruel, harsh, or unsympathetic manner

Example

She spoke unkindly about her colleague during the meeting.

她在会议期间残忍地谈论了她的同事。

B2 adjective /ˌʌndɪˈzaɪərəbl/

Undesirable

不受欢迎的; 有害的; 令人不快的

Meaning

not wanted or wished for; harmful or unpleasant

Example

The new policy had several undesirable consequences.

新政策带来了几个不受欢迎的后果。

C1 adjective /ʌnˈɒnəd/

unhonoured

未受尊敬的

Meaning

not respected or given the recognition that is deserved; treated without honor

Example

He felt unhonoured after his years of service were ignored.

他的多年服务被忽视后，他感到自己未受尊敬。

C1 noun /ˈʌp.raɪt.nəs/

Uprightness

正直; 正义

Meaning

the quality of being honest and morally correct; integrity

Example

His uprightness in business dealings earned him great respect.

他在商业中的正直赢得了很大的尊重。

C1 noun /ˌʌnprɪˈdɪktəˌbɪləti/

unpredictability

不可预测性

Meaning

The quality of being impossible to predict or anticipate.

Example

The unpredictability of the weather made the trip uncertain.

天气的不可预测性使得旅行充满不确定性。

B2 adverb /ˈʌltəmətli/

ultimately

最终

Meaning

in the end, after everything else

Example

Ultimately, we decided to go ahead with the project.

最终，我们决定继续推进该项目。

B1 adverb /ˌʌpsaɪd ˈdaʊn/

Upside-down

倒过来

Meaning

with the upper part at the bottom; in or into a reversed position

Example

The picture was hanging upside-down on the wall.

图片倒挂在墙上。

B2 adjective /ˈʌpˌhɪl/

Uphill

困难的; 需要巨大努力的; 向上的倾斜

Meaning

difficult; requiring great effort; sloping upward

Example

Learning a new language can be an uphill battle.

学习一门新语言可能是一个艰难的战斗。

B2 adverb /ʌnˈsɜːrtənli/

uncertainly

不确定地

Meaning

in a way that shows doubt or lack of certainty

Example

She glanced uncertainly at the complicated instructions.

她不确定地看着复杂的说明。

B1 noun /ʌnˈhæp.i.nəs/

unhappiness

不快乐

Meaning

the state of being unhappy; sadness or dissatisfaction

Example

Her constant unhappiness affected everyone around her.

她持续的不快乐影响了周围的每一个人。

C1 adjective /ˌʌnfɔːrθˈkʌmɪŋ/

unforthcoming

不合作的

Meaning

Not willing to talk or provide information; uncooperative.

Example

The witness was unforthcoming about what he had seen.

证人对于他所见的情况不合作。

B1 adjective /ʌnˈtru/

Untrue

错误的; 不正确的

Meaning

not true; false; incorrect

Example

His statement about the incident was completely untrue.

他关于事件的陈述完全是错误的。

B2 adjective /ʌnˌkənˈfɜːmd/

Unconfirmed

未确认; 未验证;

Meaning

not confirmed as true or definite; not verified or substantiated

Example

The report remains unconfirmed until we receive official verification.

报告在我们收到官方验证之前保持未确认状态。

C1 adjective /ˌʌnprɪˈtɛnʃəs/

unpretentious

谦虚的

Meaning

modest; not attempting to impress others with appearance or importance

Example

She lives in an unpretentious home but is very happy.

她住在一个谦虚的家里，但非常快乐。

C1 noun ˌʌndərˈprɪvəlɪdʒd ɡruːps

underprivileged groups

贫困群体

Meaning

Groups of people who lack basic necessities or advantages that are available to other members of society.

Example

Underprivileged groups benefit from social initiatives.

贫困群体从社会倡议中受益。

A2 noun /ˌʌndərˈstændɪŋ/

understanding

理解

Meaning

the ability to grasp the meaning, significance, or nature of something

Example

Her understanding of the issue was impressive.

她对这个问题的理解令人印象深刻。

B2 adjective /ˌʌnɪnˈtenʃənəl/

Unintentional

非故意的；意外的

Meaning

not done on purpose; accidental

Example

The damage to the car was unintentional.

车的损坏是非故意的。

C1 verb /ʌnˈɜːθ/

unearth

发掘

Meaning

To dig up from the ground or to discover something hidden.

Example

Archaeologists unearthed ancient artifacts at the site.

考古学家在遗址发掘了古代文物。

C1 noun /ˈʌndərˌwɜːrld/

underworld

地下世界

Meaning

The criminal world of organized crime or the mythical world of the dead.

Example

The detective spent years studying the secrets of the underworld.

侦探花了很多年研究地下世界的秘密。

B2 verb /ˈjuːtɪlaɪz/

utilize

利用

Meaning

to make practical or effective use of something

Example

The company aims to utilize solar energy for production.

公司旨在利用太阳能进行生产。

C2 adjective /ʌpˈrɔːr.i.əs/

uproarious

极其滑稽

Meaning

Extremely funny or noisy; causing loud laughter or commotion.

Example

The comedian's jokes were absolutely uproarious.

喜剧演员的笑话绝对是极其滑稽的。

B2 noun /juːˈtɪl.ə.ti/

Utility

效用; 益处; 公共服务

Meaning

the state of being useful, profitable, or beneficial; a public service

Example

The utility of solar panels increases with rising electricity costs.

随着电费上涨，太阳能板的效用也在增加。

B2 adjective /ʌnˈprɒf.ɪ.tə.bl̩/

Unprofitable

无利可图

Meaning

not yielding profit or gain; not producing financial benefit

Example

The unprofitable business was forced to close down after three years.

这个无利可图的生意在三年后被迫关闭。

C1 adjective /ˌʌndərɪkˈspoʊzd/

underexposed

曝光不足，忽视的

Meaning

insufficiently exposed to light (in photography) or not given enough attention

Example

The photo was underexposed and looked too dark.

照片曝光不足，看起来太暗了。

C1 adjective /ʌnˈtaɪərɪŋ/

Untiring

不知疲倦的; 坚持不懈的; 永不止步的

Meaning

continuing without stopping; persistent; tireless

Example

Her untiring efforts finally led to success.

她的不知疲倦的努力最终带来了成功。

B2 noun /ˌʌndəˈɡrædʒuət/

undergraduate

本科生

Meaning

a student who has not yet earned a bachelor's degree

Example

She is an undergraduate studying computer science.

她是一个学习计算机科学的本科生。

C2 verb /ʌpˈhiːv/

upheave

抬起

Meaning

to lift or raise something forcefully; to cause to rise suddenly

Example

The workers had to upheave the heavy stone to clear the path.

工人们不得不抬起重石来清理道路。

A1 pronoun /ʌs/

us

我们

Meaning

used to refer to the speaker and one or more other people as the object of a verb or preposition

Example

She gave us a gift.

她给了我们一个礼物。

B2 adverb juːˈnæn.ɪ.məs.li

unanimously

一致通过

Meaning

With the agreement of all people involved; without opposition.

Example

The proposal was unanimously accepted.

提案得到了全体一致通过。

A2 adjective /ˈʌɡ.li/

Ugly

丑陋的; 可憎的; 可怕的

Meaning

unpleasant or repulsive in appearance; morally reprehensible

Example

The old building looked ugly after years of neglect.

这座老建筑在多年疏忽之后看起来很丑。

C1 adjective /ˌʌnəˈsjuːmɪŋ/

unassuming

谦虚

Meaning

Not pretentious or arrogant; modest.

Example

Despite his success, he remained unassuming and humble.

尽管他取得了成功，他仍然谦虚和谦逊。

C1 adjective /ʌnˈtʌtʃəbəl/

Untouchable

不可触碰的; 无法批评或攻击

Meaning

not able to be touched or affected; beyond criticism or attack

Example

The CEO seemed untouchable despite the scandal.

即使有丑闻，首席执行官似乎仍然是不可触碰的。

B2 adjective /ʌnˈsuːtəbl/

Unsuitable

不适合; 不合适

Meaning

not fitting or appropriate for a particular purpose or situation

Example

This formal dress is unsuitable for a casual beach party.

这件正式的衣服不适合参加随意的海滩派对。

C1 verb /ˈʌndərkʌt/

undercut

Meaning

to sell at a lower price than a competitor; to weaken or undermine something

Example

The company tried to undercut its rivals by offering lower prices.

B2 adjective /ʌnˈhɜːrt/

unhurt

毫发无损

Meaning

Not injured or harmed.

Example

She walked away from the accident unhurt.

她在事故中毫发无损。

C1 adjective /ʌnˈseɪvəri/

unsavory

令人不快

Meaning

Disagreeable, unpleasant, or morally offensive.

Example

The politician was linked to an unsavory scandal.

那位政治家与一宗令人不快的丑闻有关。

B2 adjective /ˌʌnˈkɔːrdɪneɪtɪd/

uncoordinated

不协调; 笨拙

Meaning

lacking coordination, not well-organized or clumsy in movement

Example

His movements were uncoordinated, making him prone to accidents.

他的动作不协调，使他容易发生意外。

C2 adjective /ˌʌn.rɪˈdʒɛn.ər.ət/

unregenerate

顽固

Meaning

Not reformed or showing no signs of change; stubbornly refusing to reform or repent.

Example

He remained an unregenerate opponent of progress.

他仍然是进步的顽固反对者。

C1 adjective /ˌʌnɪmˈplɔɪəbəl/

unemployable

不适合就业

Meaning

Not able to be employed; lacking the skills or qualities necessary for employment

Example

Due to his criminal record, he was considered unemployable in most companies.

由于他的犯罪记录，他在大多数公司被认为是不适合就业。

A2 noun /ʌmˈbrɛlə/

umbrella

伞

Meaning

A device used for protection against rain or sun, typically consisting of a collapsible canopy mounted on a central rod.

Example

She opened her umbrella as it started to rain.

下雨时她打开了她的伞。

B2 adjective /ˈʌpˌraɪt/

Upright

诚实且道德正确；垂直或挺立的姿势

Meaning

honest and morally correct; vertical or erect in position

Example

She is known for being an upright and honest businesswoman.

她以诚实和正直的商业女性而闻名。

B2 adjective /ˌʌndɪˈstɜːrbd/

Undisturbed

未打扰

Meaning

not interrupted or interfered with; calm and peaceful

Example

She slept undisturbed for eight hours.

她睡了八个小时没有打扰。

B2 adjective /ʌnˈbæləns/

Unbalanced

不平衡的; 不稳定的

Meaning

not balanced; lacking stability or equilibrium; mentally unstable

Example

The unbalanced table kept wobbling.

不平衡的桌子摇晃着。

C1 noun /juːˈtoʊpiə/

utopia

乌托邦

Meaning

An imagined perfect society or place where everything is ideal.

Example

Many philosophers dreamed of creating a utopia for humanity.

许多哲学家梦想着为人类创造一个乌托邦。

B1 adjective /ʌnˈklɪər/

unclear

不清楚

Meaning

not easy to understand; vague or ambiguous

Example

The instructions were unclear, so I asked for clarification.

说明不清楚，所以我要求澄清。

C1 adverb /ʌnˈnætʃrəli/

unnaturally

不自然地

Meaning

in a way that is not natural or normal; excessively or strangely

Example

He smiled unnaturally, making everyone feel uncomfortable.

他不自然地笑了，让每个人都感到不舒服。

B2 adjective /ʌnˈtʃeɪndʒəbəl/

Unchangeable

不可改变的; 固定的;

Meaning

not able to be changed or altered; fixed and permanent

Example

The laws of physics are unchangeable principles that govern the universe.

物理法则是不变的原则，支配着宇宙。

C1 adjective /ˌʌnrɪˈfaɪnd/

unrefined

未精炼的

Meaning

not processed or purified; lacking polish or sophistication

Example

The unrefined oil must be processed before it can be used as fuel.

未精炼的石油在用作燃料之前必须进行加工。

B1 adjective /ˈɜːrbən/

urban

城市的

Meaning

related to, characteristic of, or situated in a city or town

Example

Urban areas often have higher population density than rural areas.

城市地区通常比乡村地区有更高的人口密度。

B1 adjective /ʌnˈfrɛndli/

unfriendly

不友好的

Meaning

not kind or welcoming; hostile or cold in behavior or attitude

Example

The shop owner seemed unfriendly to new customers.

店主对新顾客显得不友好。

C1 adjective /ˌʌnəˈfɛktɪd/

unaffected

不受影响的, 自然的

Meaning

Not influenced or touched by something; genuine and natural.

Example

He remained unaffected by the criticism and kept working hard.

他对批评毫不受影响，继续努力工作。

C1 adjective /ˌʌndərˈhændɪd/

underhanded

阴险

Meaning

acting or done in a dishonest or secret way

Example

They exposed the company's underhanded dealings with its suppliers.

他们揭露了公司与供应商之间的隐秘交易。

C2 noun /ˈʌn.dɚˌstɔː.ri/

understory

下层植被

Meaning

The layer of vegetation beneath the main canopy of a forest.

Example

The understory of a rainforest is home to small mammals and insects.

雨林的下层植被是小型哺乳动物和昆虫的家园。

C1 noun /ʌpˈhiːvəl/

upheaval

动荡

Meaning

a violent or sudden change or disruption to something

Example

The company faced a major upheaval after the sudden resignation of its CEO.

公司在其CEO突然辞职后经历了巨大的动荡。

B2 adjective /ʌnˈɪndʒərd/

uninjured

未受伤

Meaning

Without injury; not physically harmed.

Example

All the passengers were rescued uninjured.

所有乘客都没有受伤并被救援。

B2 verb /ˌʌndərˈskɔːr/

underscore

强调

Meaning

to emphasize or highlight something

Example

The incident underscored the need for better safety measures.

这起事件突显了更好安全措施的必要性。

A2 noun /ˌʌpˈsteəz/

Upstairs

楼上

Meaning

on or to an upper floor of a building; the upper floor or floors

Example

She went upstairs to her bedroom to rest.

她上楼去她的卧室休息。

B2 verb /ˌʌndərˈɛstɪmeɪt/

underestimate

低估

Meaning

To judge something as less important or smaller than it really is.

Example

Never underestimate the power of teamwork.

永远不要低估团队合作的力量。

A2 noun /ˈʌndərwɛr/

Under wear

内衣

Meaning

clothing worn under other clothes, next to the skin

Example

She bought new underwear from the department store.

她在百货商店买了新的内衣。

B2 adjective /ˈjuː.nɪ.faɪd/

unified

统一

Meaning

Made into a whole or joined together.

Example

A unified approach fosters better outcomes.

统一的方法促进了更好的结果。

A1 adjective /juːzd/

used

二手

Meaning

having already been used

Example

This is a used car.

这是一辆二手车。

B2 adjective /ʌnˈfeɪθ.fəl/

Unfaithful

不忠诚

Meaning

not loyal or true to a spouse, partner, or commitment

Example

He was unfaithful to his wife for many years.

他对妻子不忠诚多年。

C2 verb /ʌnˈfɛtər/

unfetter

解开束缚

Meaning

to release from restraint or restriction; to free

Example

The new law will unfetter small businesses from excessive regulations.

新法律将使小企业免于过多的规定。

B2 adjective /ˌʌnkənˈtroʊld/

uncontrolled

无法控制的

Meaning

not restrained or managed; lacking control

Example

The wildfire spread in an uncontrolled manner, causing widespread damage.

野火以无法控制的方式蔓延，造成广泛破坏。

A2 noun /ˈʌndərweər/

underwear

内衣

Meaning

Clothing worn beneath outer clothes, typically next to the skin.

Example

He bought new underwear for the trip.

他为旅行买了新的内衣。

B2 adjective /ʌn.rɪˈleɪ.tɪd/

Unrelated

无关的; 不相关

Meaning

having no connection or relationship; not connected by family ties

Example

The two incidents were completely unrelated to each other.

这两个事件完全无关。

B2 adjective /ˌʌnkənˈvɪnsɪŋ/

Unconvincing

不可信

Meaning

failing to persuade or impress; not believable or credible

Example

His excuse for being late was completely unconvincing.

他因迟到而给出的借口完全不可信。

C1 adjective /ˌʌnˈɪntɪmeɪtɪŋ/

unintimating

没有暗示

Meaning

Not giving a hint or suggestion; not indicating.

Example

His unintimating tone gave no clue of his true feelings.

他的没有暗示的语气没有透露他真正的感受。

C2 adjective /ʌnˈtʃeɪst/

Unchaste

不道德的; 不纯洁的;

Meaning

not celibate; having engaged in sexual relations; lacking moral purity

Example

The conservative society considered her behavior unchaste and improper.

保守的社会认为她的行为不道德和不合适。

C1 adjective /ˌʌndərˈsaɪzd/

undersized

尺寸过小

Meaning

Smaller than the usual or expected size.

Example

The undersized puppy struggled to keep up with its siblings.

这只尺寸过小的小狗很难跟上它的兄弟姐妹。

C2 adjective /ʌnˈblʌʃɪŋ/

Unblushing

厚颜无耻的; 放肆的

Meaning

showing no shame or embarrassment; boldly shameless

Example

He told the unblushing lie without any hesitation.

他毫不犹豫地说了那个无耻的谎言。

B1 adjective /ʌnˈfɔːr.tʃən.ət/

Unfortunate

不幸的；遗憾的

Meaning

having bad luck; regrettable or unlucky

Example

It was unfortunate that the meeting was cancelled at the last minute.

很不幸的是，会议在最后一刻被取消了。

B2 adjective /ʌnprəˈdʌk.tɪv/

Unproductive

无效的; 不起作用的

Meaning

not achieving much; not producing good results

Example

The meeting was unproductive and wasted everyone's time.

会议是无效的，浪费了大家的时间。

B2 adverb /ʌnˈplɛzəntli/

unpleasantly

令人不快地

Meaning

in a way that causes discomfort, annoyance, or displeasure; in an unfriendly or disagreeable manner

Example

The room was unpleasantly hot during the afternoon.

下午房间里热得令人不快。

C1 adjective /ˈʌpərˌmoʊst/

uppermost

最高

Meaning

situated at the highest place or most important

Example

Her family's safety was uppermost in her mind during the crisis.

她在危机期间心里最重要的是家庭的安全。

B2 verb /ˌʌndərˈteɪk/

undertake

承担

Meaning

to commit to and begin a task or project; to take on responsibility

Example

She decided to undertake a challenging project.

她决定承担一个具有挑战性的项目。

A1 adverb /ʌp/

up

向上

Meaning

towards a higher position or level

Example

He climbed up the ladder quickly.

他迅速爬上了梯子。

C1 adjective /ʌnˈsteɪtɪd/

unstated

未声明

Meaning

not expressed directly in words; implied or left unsaid

Example

The contract included several unstated expectations.

合同包括了几个未声明的期望。

A1 adjective /ˈjuːs.fəl/

Useful

有用的; 实用的

Meaning

having a beneficial purpose; practical

Example

This tool is very useful for fixing problems.

这个工具对解决问题非常有用。

C2 noun /ˈɜːrtʃɪn/

urchin

街头小孩

Meaning

a mischievous or poorly dressed child, often from the streets

Example

The ragged urchins played by the riverbank.

那些穿着破烂的街头小孩在河边玩耍。

C1 adjective /ʌlˈtɪəriər/

ulterior

隐藏的动机

Meaning

hidden or secret, often with a selfish motive

Example

He invited her with an ulterior motive.

他带着隐藏的动机邀请了她。

B1 adjective /ʌnˈedjʊkeɪtɪd/

Uneducated

未受教育的; 文盲

Meaning

lacking education; not having received formal schooling or training

Example

Many uneducated workers struggle to find well-paying jobs.

许多未受教育的工人很难找到薪水高的工作。

A1 verb /juːz/

use

使用

Meaning

to employ something for a purpose; to take advantage of

Example

I use my computer for work and entertainment.

我用我的计算机来工作和娱乐。

C1 adjective /ʌnˈsɜːrvɪsəbəl/

Unserviceable

无法使用的; 有缺陷的

Meaning

not in working order; unable to be used; defective

Example

The old computer became unserviceable after the system crash.

那台旧电脑在系统崩溃后变得无法使用。

B2 noun ˌjuːtɪlaɪˈzeɪʃən

utilization

利用

Meaning

The action of making practical and effective use of something.

Example

Increased plastic utilization calls for better waste management.

塑料的使用增加要求更好的废物管理。

C1 verb /ˌʌn.dəˈtʃɑːrdʒ/

undercharge

收取较少费用

Meaning

To charge less than the correct or fair amount.

Example

The shopkeeper accidentally undercharged me for the groceries.

店主不小心少收了我购买食品的钱。

B1 adjective /ʌnˈkaɪnd/

Unkind

残忍; 不友好

Meaning

cruel; not nice or caring toward others

Example

It was unkind of him to make fun of her appearance.

他取笑她的外貌，真是太不友善了。

C2 adjective /ʌnˈflæpəbəl/

unflappable

冷静沉着

Meaning

calm and composed, especially in difficult situations

Example

Despite the crisis, he remained unflappable and confident.

尽管面临危机，他依然保持冷静沉着，充满自信。

B2 verb /ʌnˈveɪl/

unveil

揭示

Meaning

to reveal or disclose something, especially in a formal manner

Example

The company will unveil a new product next week.

公司将在下周揭示一款新产品。

C1 noun /ˌjuːnɪˈfɔːrməti/

Uniformity

一致性；统一性；相同状态

Meaning

the quality of being uniform; consistency or sameness

Example

The uniformity of the design created a pleasing visual effect.

设计的一致性创造了一个吸引人的视觉效果。

C2 verb /ˈʌndərˌmæn/

underman

人员不足

Meaning

to supply with fewer workers or personnel than needed

Example

The hospital was undermanned during the flu outbreak.

医院在流感爆发期间人手不足。

C1 adjective /ʌnˈtoʊld/

Untold

不可计数的; 无尽的

Meaning

very great in amount or degree; countless; immeasurable

Example

The earthquake caused untold damage to the city.

地震对城市造成了无法计数的损害。

C2 noun juːˈbɪkwɪti

ubiquity

普遍性

Meaning

The fact of appearing everywhere or of being very common.

Example

The ubiquity of smartphones has transformed communication.

智能手机的普遍性改变了通信方式。

B1 adjective /ʌnˈkʊkt/

uncooked

生的

Meaning

Not cooked; in a raw state.

Example

Eating uncooked meat can be dangerous.

吃生肉可能是危险的。

C2 adjective /ʌnˈspɛərɪŋ/

unsparing

无情的

Meaning

Showing no mercy or generosity; harsh or severe.

Example

The critic was unsparing in his review of the play.

评论家在他的剧评中毫不留情。

C1 adjective /ʌnˈvaɪəbl/

unviable

不可行的

Meaning

Not capable of working successfully; not feasible or practical.

Example

The project was deemed unviable due to high costs.

由于高昂的成本，该项目被认为不可行。

B1 noun /ˈjuːnɪvɜːrs/

Universe

宇宙

Meaning

all existing matter and space; the cosmos

Example

Scientists study the universe to understand its mysteries.

科学家研究宇宙，以理解它的奥秘。

B2 adjective /ʌnˈstɛdi/

unsteady

不稳定的

Meaning

not firm or stable; likely to change or fail

Example

She felt unsteady on her feet after the long journey.

长途旅行后，她感到站立不稳。