C2 noun /ˈjuːʒəri/

usury

高利贷

Meaning

The practice of lending money at unreasonably high interest rates.

Example

The law strictly prohibits usury.

法律严格禁止高利贷。

B1 adjective /ʌnˈeɪ.bəl/

Unable

无法

Meaning

lacking the power, skill, or means to do something

Example

He was unable to attend the meeting.

他无法参加会议。

C2 adjective /ʌnˈtiːtʃəbəl/

unteachable

不可教的

Meaning

not able or willing to learn; resistant to instruction or guidance

Example

He was so stubborn that he became almost unteachable.

他非常固执，几乎变得不可教。

A2 adjective /ʌnˈhel.θi/

Unhealthy

不健康的; 有害的

Meaning

harmful to health; not in good health; detrimental to well-being

Example

Eating too much fast food is unhealthy for your body.

吃太多快餐对你的身体不健康。

B2 adjective /ʌnˈhɜːd/

Unheard

未听到的; 未知的

Meaning

not heard or listened to; not given a hearing; unknown or unfamiliar

Example

His complaints went unheard by the management.

他的投诉没有被管理层听到。

B2 adjective /ʌnˈhɛlpfəl/

unhelpful

没有帮助的

Meaning

not providing help or support; making a situation harder rather than easier

Example

His unhelpful attitude slowed down the entire project.

他没有帮助的态度拖慢了整个项目。

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 adjective /ˌʌnəˈkaʊntəbl/

unaccountable

无法解释

Meaning

Not able to be explained or justified.

Example

She felt an unaccountable fear as she entered the dark room.

她进入黑暗的房间时感到无法解释的恐惧。

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。

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 /ʌnˈkwɒl.ɪ.faɪd/

Unqualified

不合格的; 无资格的;

Meaning

not having the necessary skills or qualifications; complete or absolute

Example

He was unqualified for the engineering position due to lack of experience.

他因缺乏经验而不适合这个工程职位。

C1 adjective /ʌnˈsɪvəlaɪzd/

Uncivilized

未开化的; 野蛮的;

Meaning

not developed in terms of civilization; lacking social organization and culture; barbarous

Example

The explorers encountered an uncivilized tribe deep in the Amazon rainforest.

探险者在亚马逊雨林深处遇到一个未开化的部落。

B2 adjective /ʌnˈskɪld/

Unskilled

无技能的; 无技术的工人

Meaning

lacking technical training or ability; not requiring special skills

Example

Many unskilled workers are looking for training opportunities.

许多没有技能的工人正在寻找培训机会。

B1 verb /ʌnˈpæk/

unpack

拆开

Meaning

to remove items from a container; to explain or analyze something in detail

Example

After arriving home, she began to unpack her suitcase.

到家后，她开始拆开自己的行李箱。

C1 adjective /ʌnˈhoʊli/

Unholy

亵渎的; 罪恶的; 亵渎的

Meaning

wicked; sinful; profane

Example

The unholy alliance between the two companies caused public outrage.

这两家公司之间的不圣洁联盟引发了公众愤怒。

C1 adjective /ˌʌn.əˈdʌl.tə.reɪ.tɪd/

Unadulterated

纯净的

Meaning

not mixed or diluted with any different or extra elements; pure

Example

She felt unadulterated joy when she heard the news.

当她听到这个消息时，她感到纯净的快乐。

C1 adjective /ʌnˈmɒdɪfaɪd/

unmodified

未修改的

Meaning

not changed from its original form or state

Example

The data was used in its unmodified form for analysis.

这些数据以未修改的形式用于分析。

B1 adjective /ʌnˈfeər/

Unfair

不公平; 不正当;

Meaning

not right or just; treating people in a way that favors some over others

Example

It's unfair to blame her for something she didn't do.

指责她做了她没有做的事是不公平的。

B1 adjective /ˌʌnˈɪntrəstɪŋ/

uninteresting

无趣的

Meaning

not holding attention or curiosity; boring

Example

The lecture was uninteresting and difficult to stay focused on.

这次讲座很无趣，很难集中注意力。

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 /ˌʌnˈnoʊ.tɪst/

Unnoticed

未被注意到; 被忽视

Meaning

not seen or observed; ignored

Example

His hard work went unnoticed by his manager.

他的辛勤工作没有被经理注意到。

B2 adverb /ʌnˈnesəserəli/

Unnecessarily

不必要地

Meaning

to a greater extent than is needed; without necessity

Example

Don't worry unnecessarily about the exam.

不要为考试不必要地担心。

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。

C1 adjective /ˌʌnkɒnstɪˈtuːʃənəl/

Unconstitutional

违宪的

Meaning

not in accordance with a political constitution; violating constitutional principles

Example

The court declared the new law unconstitutional.

法院宣布这项新法律违宪。

B2 verb ˈjuːnɪfaɪ

unify

统一

Meaning

To make or become united, uniform, or whole; to bring together into a single unit.

Example

Adolescents unify with peers for social acceptance.

青少年为了社会接纳与同伴统一。

A2 adjective /ʌnˈlʌki/

Unlucky

倒霉; 不幸运

Meaning

having bad luck; unfortunate

Example

He was unlucky to miss the winning shot.

他很倒霉错过了获胜的投篮。

C1 adjective ʌnˈpær.ə.leld

Unparalleled

无与伦比

Meaning

Having no equal; unmatched, peerless, and supreme in quality or achievement.

Example

The unparalleled beauty of the Taj Mahal amazes visitors.

泰姬陵无与伦比的美丽使游客惊叹。

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。

C1 adjective ʌnˈwɔːr.rən.tɪd

unwarranted

不合理的

Meaning

Not justified or necessary; without good reason.

Example

His anger toward the staff was completely unwarranted.

他对员工的愤怒是完全不合理的。

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。

B2 adjective /ʌnˈɡreɪt.fəl/

Ungrateful

忘恩负义

Meaning

not feeling or showing thanks for something done or given; not appreciating kindness

Example

She felt he was ungrateful for all the help she had given him.

她觉得他对她给予的所有帮助都忘恩负义。

B1 adjective /ˌʌnɪkˈspektɪd/

Unexpected

出乎意料的; 令人惊讶的

Meaning

not expected or anticipated; surprising

Example

The unexpected news left everyone speechless.

出乎意料的消息让所有人都哑口无言。

B1 adjective ʌnˈplænd

unplanned

未计划的

Meaning

Not planned or arranged in advance; happening spontaneously without preparation.

Example

Unplanned urbanization contributes to environmental issues.

无计划的城市化会加剧环境问题。

B2 adjective /ˌʌnrɪˈlaɪəbl/

Unreliable

不可靠的; 不能被信任或依赖

Meaning

not dependable; not able to be trusted or relied upon

Example

The old car is unreliable and breaks down frequently.

这辆老车不可靠，常常坏掉。

C2 verb /ˌʌn.dɪˈsiːv/

undeceive

解惑

Meaning

To free someone from a misconception or false belief.

Example

She tried to undeceive him about the false rumors.

她试图让他摆脱这些错误的谣言。

C2 noun /ʌnˈkloʊðɪŋ/

unclothing

脱衣

Meaning

the act or process of removing clothing

Example

The child quickly ran inside for unclothing after playing in the mud.

孩子在泥地玩耍后迅速跑进去脱衣。

B1 adjective /ʌnɪmˈplɔɪd/

Unemployed

失业

Meaning

without a job; not having paid work

Example

He has been unemployed for six months now.

他已经失业六个月了。

C2 verb /ʌnˈɑːrm/

unarm

解除武装

Meaning

to remove weapons from someone or to deprive of means of attack or defense

Example

The soldiers were ordered to unarm the prisoners.

士兵接到命令解除囚犯的武装。

C2 adjective /ʌnˈkɒnʃənəbl/

unconscionable

不合理的

Meaning

shockingly unfair or unreasonable

Example

The company made unconscionable profits from the crisis.

公司从危机中获得了不合理的利润。

B2 adjective /ˌʌndɪˈsaɪdɪd/

Undecided

未决定的; 不确定的

Meaning

not having made a decision; uncertain

Example

She was undecided about which college to attend.

她对于选择哪个大学感到未决定。

C1 adjective /ʌnˈsiːmli/

unseemly

不得体

Meaning

Not proper or appropriate in behavior or appearance; unbecoming.

Example

His unseemly remarks embarrassed everyone at the dinner table.

他不得体的言论让晚餐桌上的每个人都感到尴尬。

B2 adjective /ʌnˈθɪŋkəbl/

Unthinkable

难以想象的

Meaning

impossible to conceive or imagine; beyond belief or consideration

Example

It was unthinkable that such a tragedy could happen in our peaceful town.

在我们和平的小镇上发生这样一场悲剧，简直是难以想象的。

B2 noun /ʌnˈkaɪndnəs/

unkindness

不友善

Meaning

lack of kindness; cruel or inconsiderate behavior

Example

His unkindness hurt her feelings deeply.

他的不友善深深伤害了她的感情。

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 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。

B2 adjective /ˌʌnəˈweər/

Unaware

无意识的; 不知道的; 没有意识

Meaning

not knowing or realizing; having no knowledge of something

Example

She was completely unaware of the danger.

她完全没有意识到危险。

B1 verb /ʌnˈræp/

unwrap

拆开

Meaning

remove wrapping or covering from something; reveal something gradually or clearly

Example

She carefully unwrapped the gift with excitement.

她兴奋地小心拆开了礼物。

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。

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。

C2 adjective /ʌnˈmɪtɪɡeɪtɪd/

unmitigated

完全

Meaning

absolute; not lessened or moderated

Example

The meeting was an unmitigated disaster.

会议是一次完全的灾难。

C2 adjective /ˈʌndjʊləs/

undulous

波浪形的

Meaning

Having a wavy surface or form.

Example

The artist painted the undulous sea at sunset.

艺术家在日落时画了波浪形的海洋。

C1 adjective /ʌnˈspiːkəbl/

unspeakable

难以形容

Meaning

too bad or shocking to be expressed in words

Example

The survivors endured unspeakable horrors during the war.

幸存者在战争中忍受了难以形容的恐怖。

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。

B2 adjective /ʌnˌkənˈdɪʃ.ən.əl/

Unconditional

无条件的

Meaning

not subject to any conditions; complete and absolute

Example

She offered her unconditional support to her friend in need.

她在朋友需要时提供了无条件的支持。

B2 adjective /ʌnˈtʃeɪndʒɪŋ/

unchanging

不变的

Meaning

remaining the same over time; not changing

Example

Her love for her family was unchanging throughout the years.

她对家人的爱多年来始终不变。

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。

C2 noun /ˌjuːnɪˈtɛəriən/

unitarian

一神论者

Meaning

A person who believes that God exists as one entity rather than as a Trinity; a member of a religious denomination that emphasizes individual freedom of belief.

Example

The Unitarian church is known for its inclusive and open-minded approach.

一神论教会以其包容和开放的思想方式而闻名。

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。

A1 noun /ˈʌŋkəl/

uncle

叔叔/舅舅

Meaning

the brother of one's father or mother

Example

My uncle is visiting us next week.

我的叔叔下周会来看我们。

C2 adjective /ˈʌŋk.tʃu.əs/

unctuous

阿谀奉承

Meaning

Excessively flattering or ingratiating; oily in texture.

Example

His unctuous tone made everyone uncomfortable.

他那种阿谀奉承的语气让每个人都感到不舒服。

C2 verb /ʌnˈjoʊk/

unyoke

解开

Meaning

To release from a yoke or to free from restraint or obligation.

Example

The farmer unyoked the oxen after a long day of work.

农民在长时间工作后解开了牛的套索。

B2 adjective /ʌnhaɪˈdʒiːnɪk/

Unhygienic

不卫生的；缺乏适当的卫生

Meaning

not clean; lacking proper sanitation

Example

The restaurant was closed due to unhygienic conditions in the kitchen.

由于厨房不卫生的条件，餐厅被关闭。

B2 verb /ɜːrdʒ/

urge

催促

Meaning

to strongly encourage or try to persuade someone to do something

Example

Doctors urge patients to exercise regularly.

医生鼓励病人定期锻炼。

C2 adjective /ʌnˈælɔɪd/

unalloyed

纯净

Meaning

Pure, complete, and not mixed with anything else.

Example

She felt unalloyed joy at the news of her success.

她听到成功的消息时感到纯粹的喜悦。

A1 noun /ˌjuːnɪˈvɜːrsɪti/

university

大学

Meaning

an institution of higher education and research, which grants academic degrees

Example

She is studying law at the university.

她在大学学习法律。

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。

B2 adjective /ˌʌnəˈveɪləbəl/

unavailable

不可用

Meaning

Not able to be obtained, reached, or used; not present or accessible.

Example

The manager was unavailable to take calls during the meeting.

经理在会议期间不可用，无法接听电话。

B2 adjective /ˌʌnɪnˈfɔːrmd/

uninformed

不了解情况的

Meaning

lacking knowledge or awareness about a particular subject; not educated or informed

Example

The decision was made by an uninformed committee.

这个决定是由一个不了解情况的委员会做出的。

B1 adjective /ʌnˈwel/

Unwell

不舒服; 生病

Meaning

not in good health; feeling sick or ill

Example

She has been feeling unwell since yesterday.

她从昨天开始感到不舒服。

C2 adjective /ɜːrˈbeɪn/

urbane

都市的

Meaning

showing polished manners, refinement, and sophistication

Example

He was an urbane gentleman who charmed everyone at the party.

他是一个都市绅士，在派对上迷住了所有人。

B2 verb /ˌʌndərˈmaɪn/

undermine

削弱

Meaning

to gradually weaken or damage something or someone

Example

Constant criticism can undermine a child's confidence.

持续的批评可能会削弱孩子的自信心。

A2 adjective /ʌnˈtaɪdi/

Untidy

凌乱的; 无序的;

Meaning

not neat or orderly; messy and disorganized

Example

Her untidy room was filled with clothes scattered everywhere.

她凌乱的房间充满了四处散落的衣服。

C2 verb /ʌpˈbreɪd/

upbraid

斥责

Meaning

To scold or criticize someone harshly.

Example

The teacher upbraided the student for being late again.

老师因为学生再次迟到而训斥了他。

C2 adjective /ˌʌltrəˈmʌndeɪn/

ultramundane

超凡

Meaning

Relating to things beyond the physical world; supernatural or transcendental.

Example

Philosophers often discuss ultramundane realities beyond human perception.

哲学家们常常讨论超越人类感知的超凡现实。

C1 noun ˈʌp.raɪ.zɪŋ

uprising

起义

Meaning

An act of resistance or rebellion; a revolt against an authority or government.

Example

The uprising marked the beginning of the revolution.

起义标志着革命的开始。

C1 adjective /ʌnˈmaɪndfəl/

Unmindful

不留心的; 疏忽的;

Meaning

not paying attention; careless; heedless

Example

She was unmindful of the danger around her.

她没有注意到周围的危险。

B2 adjective /ʌnˈsiːn/

Unseen

看不见的；未曾看到或注意到的

Meaning

not previously seen or noticed; invisible; hidden

Example

The unseen forces of nature can be very powerful.

自然界的看不见的力量可能非常强大。

B1 verb /juˈnaɪt/

unite

联合

Meaning

to join together or combine; to bring people or things together

Example

The crisis helped unite the community.

危机帮助团结了社区。

C1 adjective /ʌnˈmænɪdʒəbəl/

Unmanageable

无法控制的; 失控

Meaning

difficult or impossible to control or handle

Example

The large class became unmanageable without proper supervision.

没有适当的监督，班级变得无法控制。

B2 adverb /ʌnˈwɪlɪŋli/

unwillingly

不情愿地

Meaning

in a way that shows reluctance or lack of desire; not willingly

Example

She unwillingly agreed to attend the meeting.

她不情愿地同意参加会议。

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 + noun ʌnˈpresɪdentɪd ˈnɒlɪdʒ

unprecedented knowledge

前所未有的知识

Meaning

Information or understanding that has never been obtained or achieved before.

Example

Artemis will provide unprecedented knowledge about the solar system.

阿尔忏将提供关于太阳系的前所未有的知识。

B2 noun ˈjuːnəti

unity

团结

Meaning

The state of being united or joined as a whole.

Example

Unity among people led to victory.

人们之间的团结带来了胜利。

C1 adjective /ʌnˈruːli/

Unruly

不守规矩的; 乱七八糟的;

Meaning

difficult to control or manage; disorderly and disruptive

Example

The unruly crowd refused to follow the safety instructions.

那群无法控制的人群拒绝遵循安全指令。

C2 adjective /ʌnˈfeɪnd/

unfeigned

真诚

Meaning

genuine; not pretended or insincere

Example

She expressed unfeigned joy at her friend's success.

她在朋友的成功上表达了真诚的喜悦。

C1 adjective /ʌnˈkɛmpt/

unkempt

邋遢

Meaning

Having an untidy or disheveled appearance.

Example

He looked unkempt after sleeping outdoors all night.

他睡了一整晚露天后，看起来邋遢。

B2 adjective /ˌjuːnɪˈvɜːrsəl/

Universal

普遍的

Meaning

applicable to all cases; existing everywhere

Example

Music is a universal language that everyone understands.

音乐是一种普遍的语言，人人都能理解。

C2 adjective /ʌnˈwiːldi/

unwieldy

笨重

Meaning

Difficult to carry or move because of its size, shape, or weight.

Example

The box was too unwieldy to carry up the stairs.

这个盒子太笨重了，无法把它提上楼梯。

B2 adjective /ʌnˈendɪŋ/

Unending

无尽的

Meaning

continuing forever; without end

Example

The unending rain made the day feel gloomy.

无尽的雨让这一天显得阴沉。

B2 adjective /ˈʌt.moʊst/

Utmost

最极; 极限

Meaning

greatest; most extreme; maximum possible

Example

She showed utmost care while handling the fragile items.

她在处理脆弱物品时表现出最大的关心。

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。

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。

C2 verb /ˌʌndərˈɡɜːrd/

undergird

支持，强化

Meaning

to provide support or foundation for; to strengthen

Example

Strong values undergird a healthy society.

强大的价值观支撑着一个健康的社会。

B2 adjective /ˈʌl.tɪ.mət/

Ultimate

最终的; 极致的; 终极的

Meaning

being the best or most extreme example of its kind; final; last

Example

This is the ultimate test of your skills.

这是你技能的终极考验。

B2 adjective /ʌnˈiːzi/

Uneasy

不安的; 焦虑的; 不舒服的

Meaning

worried; anxious; uncomfortable; restless

Example

She felt uneasy about walking alone at night.

她在夜晚独自行走时感到不安。

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。

C1 adjective /ʌnˈkleɪmd/

Unclaimed

未认领的; 未要求的; 被遗弃或无主的

Meaning

not claimed by anyone; not demanded or requested; abandoned or ownerless

Example

The unclaimed luggage was stored in the airport's lost property department.

未认领的行李被存放在机场的失物招领处。

B2 adjective /ʌnˈlɪmɪtɪd/

unlimited

无限

Meaning

without any limits or restrictions

Example

The internet plan offers unlimited data for the whole month.

该互联网计划提供整个一个月的无限数据。

C2 adjective /ˌʌnɪmˈpiːtʃəbl/

unimpeachable

无可指摘

Meaning

Not able to be doubted, questioned, or criticized; completely trustworthy.

Example

She is known for her unimpeachable honesty.

她因其无可指摘的诚实而闻名。

B2 adjective /ʌnˈriːdəbl/

unreadable

难以辨认的

Meaning

not able to be read or understood clearly; illegible

Example

The doctor’s handwriting was completely unreadable.

医生的字迹完全难以辨认。

B1 adjective /ˈʌpər/

upper

上层

Meaning

higher in position or rank

Example

The upper floor of the building is under renovation.

建筑物的上层正在翻修。

B2 noun /ˈɜː.dʒən.si/

Urgency

紧急

Meaning

the quality of requiring immediate action or attention; pressing importance

Example

The urgency of the situation required immediate medical attention.

情况的紧急性要求立即的医疗关注。

B2 adjective /ˌʌndɪˈnaɪəbl/

Undeniable

不容置疑

Meaning

impossible to deny or dispute; clearly true

Example

The evidence of his guilt was undeniable.

他的罪行证据是不容置疑的。

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。

C1 adjective /ˌjuːnɪˈsɛljʊlər/

unicellular

单细胞

Meaning

Consisting of a single cell.

Example

Amoebas are unicellular organisms.

变形虫是单细胞生物。

C2 noun /ˈʌŋɡwənt/

unguent

药膏

Meaning

A soothing or healing ointment applied to the skin.

Example

The doctor applied an unguent to heal the burn.

医生涂抹了药膏来治愈烧伤。

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。

C1 noun /ʌnˈfeɪθfʊlnəs/

unfaithfulness

不忠

Meaning

the quality of being disloyal or not faithful; breach of trust or fidelity

Example

His unfaithfulness led to the end of their marriage.

他的不忠导致了他们婚姻的结束。

前所未有

Meaning

Never done or known before; without previous example.

Example

Unprecedented advancements in science changed human lives.

科学上的前所未有的进展改变了人类的生活。