fetus
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C1 noun /ˈfiːtəs/

fetus

胎儿
Meaning
an unborn or unhatched offspring in the womb or egg
Example
The doctor explained the development of the fetus during pregnancy.
医生解释了胎儿在怀孕期间的发展。
A2 noun /flʌd/

Flood

洪水
Meaning
an overflow of a large amount of water beyond its normal limits
Example
The heavy rain caused a flood in the village.
暴雨导致村庄发生了洪水。
C1 noun /ˈfoʊ.kəs ˈtræk.ɪŋ/

focus tracking

聚焦追踪
Meaning
A technique of monitoring and maintaining attention on specific tasks or goals.
Example
Proper focus tracking improves productivity.
适当的聚焦追踪可以提高生产力。
C2 noun /ˈfoʊ.li.oʊ/

folio

大书或手稿
Meaning
A sheet of paper folded once to form two leaves (four pages) of a book; also a term for a large book or manuscript.
Example
The library houses an ancient Shakespeare folio.
图书馆里有一本古老的莎士比亚大书。
C2 noun /fɔːrˈbɛrəns/

forbearance

宽容
Meaning
Patient self-control; restraint and tolerance, especially in difficult situations.
Example
She showed remarkable forbearance during the heated argument.
她在激烈的争论中表现出了非凡的宽容。
C2 noun /ˈfɪli/

filly

小母马
Meaning
a young female horse
Example
The filly ran swiftly across the meadow.
这匹小母马在草地上跑得很快。
C2 adjective /ˈfraɪəbl/

friable

脆弱
Meaning
Easily crumbled or reduced to powder.
Example
The old brick wall was friable and broke apart at a touch.
那堵老砖墙是脆弱的，轻轻一碰就破裂了。
B2 noun /ˈfriːdəm ˌfaɪtər/

freedom fighter

自由斗士
Meaning
a person who takes part in an armed or political struggle to achieve freedom or independence for their people or country
Example
The freedom fighter dedicated his life to the liberation of his homeland.
这位自由斗士把一生献给了祖国的解放。
A1 noun /fʊt/

Foot

脚
Meaning
the lower extremity of the leg that is in direct contact with the ground in standing or walking
Example
She hurt her foot while running.
她在跑步时扭伤了脚。
A2 verb ˈfoʊkəs

focus

集中
Meaning
To concentrate attention or effort on something; to direct one's attention or efforts towards a particular activity, subject, or problem.
Example
Focus on what truly matters to simplify your life.
专注于真正重要的事情，让生活变得更简单。
C1 verb /fɔːrˈɡoʊ/

forgo

放弃
Meaning
to decide not to do or have something
Example
She decided to forgo dessert to maintain her diet.
她决定放弃甜点以保持她的饮食。
B2 noun /ˈfækəlti/

faculty

能力, 系
Meaning
an inherent mental or physical ability; a division of a university
Example
She has a remarkable faculty for languages.
她有惊人的语言能力。
C1 noun /fiˈæs.koʊ/

fiasco

彻底失败
Meaning
a complete failure, especially a ludicrous or humiliating one
Example
The event turned into a complete fiasco due to poor planning.
由于糟糕的规划，活动变成了彻底的失败。
C1 adverb /ˈfɜː.vənt.li/

Fervently

热情地; 激情地;
Meaning
with passionate intensity; ardently; with great emotion or enthusiasm
Example
She fervently hoped that her dreams would come true.
她热情地希望她的梦想能成真。
C1 noun /ˈfʌŋɡəs/

fungus

真菌
Meaning
a spore-producing organism feeding on organic matter, including molds, yeast, and mushrooms
Example
A strange fungus was growing on the old tree.
一种奇怪的真菌在老树上生长。
B1 noun /fiː/

fee

费用
Meaning
A payment made for a service or privilege.
Example
The lawyer charged a high fee for his services.
律师为他的服务收取了高额费用。
C1 verb /ˈfæbrɪkeɪt/

fabricate

编造
Meaning
to invent or concoct something, often with the intent to deceive; or to construct or manufacture
Example
The witness fabricated his testimony to protect himself.
证人为了保护自己而编造了他的证词。
A2 noun /fæn/

Fan

粉丝; 扇子
Meaning
a person who has a strong interest in or admiration for a particular person or thing; a device for creating air current
Example
She is a huge fan of classical music and attends every concert in the city.
她是古典音乐的忠实粉丝，并参加城市中的每一场音乐会。
C1 noun /fɪˈnɛs/

finesse

精妙, 技巧, 高雅
Meaning
Subtlety and skill; refinement and delicacy in performance or artistry.
Example
The artist painted with great finesse.
艺术家以极高的精妙感画画。
B2 noun ˈfrʌn.tɪərz

frontiers

边界
Meaning
The extreme limit of settled land beyond which lies wilderness; the limits of knowledge or achievement in a particular field.
Example
The project pushes the frontiers of space exploration.
这个项目推动了太空探索的边界。
B2 verb /fʊlˈfɪl/

fulfil

实现
Meaning
to complete or achieve something that was expected or promised; to satisfy a requirement or desire
Example
She worked hard to fulfil her dream of becoming a doctor.
她努力工作以实现成为医生的梦想。
A2 adjective /ˈfaɪ.nəl/

Final

最后的; 决定性的; 终极的
Meaning
last; concluding; decisive; ultimate
Example
This is the final exam of the semester.
这是本学期的最终考试。
C1 adjective, adverb (informal, vulgar) /ˈfʌkɪŋ/

fucking

他妈的 (粗俗词语用于强调)
Meaning
used for emphasis, often expressing anger or frustration (vulgar slang)
Example
It was a fucking disaster!
这真是个他妈的灾难！
A2 noun, verb /fuːl/

fool

傻瓜
Meaning
a silly or stupid person; to trick someone
Example
He felt like a fool after believing the prank.
他在相信恶作剧之后觉得自己像个傻瓜。
C1 noun ˌfɔːtɪfɪˈkeɪʃn

fortification

防御工事
Meaning
A defensive wall or other reinforcement built to strengthen a place against attack.
Example
The fortifications protected the city.
防御工事保护了城市。
C1 noun /ˈflæt.ər.i/

Flattery

恭维
Meaning
excessive and insincere praise, given especially to further one's own interests
Example
His constant flattery made everyone suspicious of his true motives.
他不断的恭维使大家怀疑他的真实动机。
C2 adjective /ˈfiːbəlˌmaɪndɪd/

feebleminded

愚蠢或心智薄弱
Meaning
lacking intelligence or mental capacity; foolish or weak-minded
Example
The feebleminded man struggled to understand basic instructions.
那个心智薄弱的人很难理解基本的指示。
A1 noun ˈfjuː.tʃər

future

未来
Meaning
The time or a period of time following the moment of speaking or writing; time regarded as still to come.
Example
Future projects depend on strategic planning.
未来的项目依赖于战略规划。
C1 noun /ˈfɔːls.hʊd/

Falsehood

虚伪; 谎言
Meaning
the state of being untrue; a lie
Example
The politician was caught spreading falsehoods about his opponent.
那位政治家被抓到散播关于对手的谎言。
C2 noun /ˈfrækɑː/

fracas

纷争
Meaning
A noisy disturbance or quarrel.
Example
The fracas outside the bar drew the attention of the police.
酒吧外的纷争引起了警察的注意。
C2 verb /flɛdʒ/

fledge

飞翔
Meaning
To develop wing feathers large enough for flight; to bring up until able to fly.
Example
The young birds will fledge in a few weeks.
年轻的鸟将在几周内学会飞行。
A2 noun /fraɪd raɪs/

Fried rice

炒饭
Meaning
a dish of cooked rice that has been stir-fried in a wok or frying pan
Example
We ordered chicken fried rice from the Chinese restaurant.
我们从中国餐馆订了鸡肉炒饭。
C2 noun /ˈfɜːrlɔːŋ/

furlong

距离单位（220码或大约201米）
Meaning
a unit of distance equal to 220 yards or about 201 meters
Example
The horse ran a furlong before slowing down.
马跑了一个弗隆后才减速。
C1 noun /ˈfjuː.də.lɪ.zəm/

feudalism

封建主义
Meaning
the social system in medieval Europe in which people worked and fought for nobles who gave them protection and land in return
Example
Feudalism shaped the political structure of medieval Europe.
封建主义塑造了中世纪欧洲的政治结构。
B1 noun faʊnˈdeɪʃən

foundation

基础
Meaning
The lowest load-bearing part of a building, typically below ground level.
Example
The foundation of the building was laid with strong materials.
建筑物的基础是用坚固的材料铺设的。
C1 noun, verb /fɔːrd/

ford

浅滩
Meaning
A shallow place in a river where one can cross; to cross a river at such a place.
Example
The travelers decided to ford the river at dawn.
旅行者决定在黎明时分穿越河流。
A2 adjective /fəˈmɪl.jər/

Familiar

熟悉的; 了解的; 非正式且友好的
Meaning
well-known; easily recognized; having knowledge of; informal and friendly
Example
This song sounds familiar to me.
这首歌听起来对我很熟悉。
B1 noun ˈfæmɪli triː

Family Tree

家谱
Meaning
A diagram showing the relationships between people in several generations of a family.
Example
Creating a family tree helps understand family history.
创建家谱有助于理解家庭历史。
C1 adjective /ˈfrɪvələs/

frivolous

轻浮
Meaning
Not having any serious purpose or value; silly or unimportant.
Example
She dismissed the frivolous complaint quickly.
她迅速驳回了这个轻浮的投诉。
B2 verb /fliː/

flee

逃跑
Meaning
To run away from danger or a threatening situation.
Example
The villagers had to flee during the flood.
村民们在洪水期间不得不逃离。
C2 noun /ˈfʌŋkʃəˌnɛri/

functionary

职员
Meaning
a person who has official duties in an organization, especially one with little authority
Example
The minor functionary was responsible for filing reports.
次要的职员负责提交报告。
C2 noun /fluːk/

fluke

侥幸
Meaning
A stroke of luck; an unexpected piece of good fortune.
Example
Winning the lottery was a complete fluke.
中彩票简直就是一次完全的侥幸。
C2 noun /ˈfaɪnəri/

finery

昂贵或精致的衣服
Meaning
expensive or elaborate clothes, decorations, or accessories
Example
She attended the party in her finest finery.
她穿着最好的衣服参加了聚会。
C2 noun /ˈfiːəlti/

fealty

忠诚与效忠
Meaning
loyalty or allegiance, especially to a sovereign or lord
Example
The knight swore fealty to his king.
骑士向国王宣誓效忠。
B1 noun /ˈflaʊər veɪs/

Flower-vase

花瓶
Meaning
a decorative container used to hold cut flowers
Example
She placed beautiful roses in the flower vase on the table.
她把美丽的玫瑰放进了桌子上的花瓶里。
C2 adjective /ˈflɒrɪd/

florid

过度装饰的 / 红润
Meaning
Having a red or flushed complexion; or excessively ornate and intricate.
Example
The speaker’s florid style made the lecture hard to follow.
演讲者过度装饰的风格使得讲座难以理解。
C1 noun /ˈfɔːreɪ/

foray

突袭 / 初步尝试
Meaning
A sudden short attack or attempt, especially into new activity or territory.
Example
The company made its first foray into the international market.
公司首次进军国际市场。
C1 noun /ˈfɔːrˌθɔːt/

forethought

预见
Meaning
careful consideration of what will be necessary or may happen in the future
Example
With a little forethought, we could have avoided the problem.
稍微有一点预见性，我们本可以避免这个问题。
B2 adjective /ˌfjuːtʃəˈrɪstɪk/

futuristic

未来主义的
Meaning
Having or involving very modern technology or design that is advanced beyond what is currently available
Example
Futuristic technologies are transforming industries worldwide.
未来主义技术正在改变全球的行业。
B2 verb /fɔɪl/

foil

挫败
Meaning
To prevent something (especially a plan) from succeeding.
Example
The police foiled the robbery attempt.
警方挫败了抢劫企图。
B2 verb /feɪnt/

faint

昏厥
Meaning
to lose consciousness for a short time because of a temporary lack of oxygen to the brain
Example
He felt dizzy and fainted in the heat.
他感到头晕，并因高温而昏倒。
B2 verb /flɜːrt/

flirt

Meaning
to behave as if you are attracted to someone, but not in a serious way
Example
She often flirts with her colleagues at work.
C2 noun /ˈfrɛs.koʊ/

fresco

壁画
Meaning
A painting done rapidly in watercolor on wet plaster so that the colors penetrate the surface
Example
The church walls were decorated with beautiful frescoes.
教堂的墙壁装饰着美丽的壁画。
C1 noun fɔːlt ˈtɒl.ər.əns

fault-tolerance

容错性
Meaning
The ability of a system to continue operating properly in the event of the failure of some of its components.
Example
Fault-tolerance ensures dependable systems.
容错性确保了可靠的系统。
C2 noun /feɪnt/

feint

假动作, 伪装动作
Meaning
a deceptive or pretended movement, especially in fighting or sports
Example
The boxer made a feint to the left before striking to the right.
拳击手在打右拳之前做了一个左侧的假动作。
A2 noun /ˈfoʊldər/

folder

文件夹
Meaning
a container or directory used to store and organize papers or digital files
Example
I saved all the photos in a separate folder.
我把所有照片保存在一个单独的文件夹里。
C1 noun /fəˈrɒs.ə.ti/

ferocity

凶猛，暴力，强度
Meaning
The state or quality of being ferocious; extreme fierceness or violence.
Example
The storm's ferocity was devastating.
风暴的猛烈程度是毁灭性的。
B2 noun /ˈfɛmənɪst/

feminist

女性主义者
Meaning
a person who supports equal rights and opportunities for women and men
Example
She proudly calls herself a feminist and fights for gender equality.
她自豪地称自己为女性主义者，并为性别平等而奋斗。
C1 noun flɛər

flair

天赋
Meaning
A natural ability to do something well.
Example
She has a flair for design, always creating visually stunning work.
她有设计的天赋，总是创造出视觉上令人印象深刻的作品。
C2 verb /ˈfjuːmɪˌɡeɪt/

fumigate

熏蒸
Meaning
to disinfect or purify an area by using chemical fumes
Example
They fumigated the warehouse to kill the insects.
他们对仓库进行了熏蒸处理，以消灭昆虫。
C1 adjective /ˈfuːlpruːf/

foolproof

万无一失
Meaning
Designed to be very easy to use or understand, leaving no possibility of failure or error.
Example
The new software has a foolproof installation process.
这款新软件具有万无一失的安装过程。
A2 adjective /fɔːls/

False

虚假; 错误; 欺骗性; 人造
Meaning
not true; incorrect; deceptive; artificial
Example
The witness gave false testimony in court.
证人给出了虚假的证词。
A2 adjective /faɪn/

Fine

好的; 极好的; 薄的; 纤细的; 高质量的
Meaning
good; excellent; thin; delicate; high quality
Example
The weather is fine today.
今天天气很好。
C1 noun ˌfræɡ.mənˈteɪ.ʃən

fragmentation

碎片化
Meaning
The process or state of breaking or being broken into fragments.
Example
Habitat fragmentation threatens many species.
栖息地的碎片化威胁着许多物种。
C1 verb /fɔːrˈkloʊz/

foreclose

止赎
Meaning
to take possession of a property due to the owner's failure to keep up mortgage payments
Example
The bank decided to foreclose on the property after months of missed payments.
银行在错过几个月付款后决定没收财产。
C2 adjective /fəˈlɪsɪtəs/

felicitous

恰当的, 合适的或令人愉快的; 由好运或幸福标志
Meaning
well-chosen, appropriate, or pleasing; marked by good fortune or happiness
Example
She made a felicitous remark that lightened the mood.
她做了一个恰到好处的评论，使气氛轻松了。
A2 adverb /ˈfaɪ.nəl.i/

Finally

终于
Meaning
at last; after a long time; in the end; as the last point
Example
After years of hard work, she finally achieved her goal.
经过多年的努力工作，她终于达成了自己的目标。
C1 verb /ˈfɜːr.tɪ.laɪz/

fertilize

施肥
Meaning
to make soil or land more fertile by adding substances
Example
Farmers fertilize the fields to increase crop yield.
农民施肥以增加作物产量。
C1 noun /frɪˈvɒləti/

frivolity

轻浮
Meaning
Lack of seriousness; silly or trivial behavior.
Example
The teacher discouraged frivolity during the exam.
老师在考试期间阻止了轻浮行为。
C2 noun /floʊ/

floe

浮冰
Meaning
a large sheet of floating ice
Example
The polar bears rested on the ice floe.
北极熊在浮冰上休息。
C2 noun /fəˈlɪsɪti/

felicity

幸福
Meaning
intense happiness; the ability to find appropriate expression for one's thoughts
Example
She was known for her felicity in conversation and cheerful nature.
她因在对话中的幸福和开朗的性格而闻名。
B1 verb /fərˈbɪd/

forbid

禁止
Meaning
to order someone not to do something
Example
The school forbids smoking on campus.
学校禁止在校园内吸烟。
C2 adjective /fɪˈdjuːʃəl/

fiducial

信任的，作为参考标准的
Meaning
based on trust or confidence; serving as a standard of reference
Example
The fiducial point on the map ensures accurate measurements.
地图上的菲杜西亚尔点确保了精确的测量。
B2 noun /ˈfræɡ.mənt/

Fragment

碎片; 片段;
Meaning
a small part broken or separated off something; an incomplete or isolated portion
Example
Archaeologists found fragments of ancient pottery buried in the soil.
考古学家在土壤中发现了古代陶器的碎片。
B2 noun /ˈfɔːrmjələ/

formula

公式
Meaning
a fixed method for doing something; a mathematical or chemical rule expressed in symbols
Example
The scientist discovered a new formula for the medicine.
科学家发现了一种新的药物公式。
C1 noun /ˈfreɪlti/

frailty

脆弱
Meaning
The condition of being weak, delicate, or easily broken.
Example
Old age often comes with physical frailty.
衰老通常伴随着身体的脆弱。
B2 noun /fɪɡ/

Fig

无花果
Meaning
a soft sweet fruit that is purple or green on the outside and has many small seeds
Example
The fig tree in our backyard produces delicious fruits every summer.
我们后院的无花果树每年夏天都能结出美味的果实。
C2 adjective /ˈfɛkləs/

feckless

无能的, 不负责任的
Meaning
lacking initiative or strength of character; irresponsible
Example
His feckless attitude at work caused several missed deadlines.
他在工作中的无能态度导致了多个错过的最后期限。
C2 verb /ˈfɒn.dəl/

fondle

抚摸
Meaning
To stroke or caress lovingly or gently.
Example
She fondled the kitten gently in her lap.
她轻柔地抚摸着她膝盖上的小猫。
C2 noun /ˈfiːæt/

fiat

法令，命令
Meaning
an official order or decree; authoritative command
Example
The new policy was enacted by royal fiat.
新政策通过皇帝的命令实施。
C2 noun /fɪntʃ/

finch

雀鸟（小型歌唱鸟）
Meaning
a small songbird with a short, stout bill
Example
A colorful finch perched on the branch singing sweetly.
一只五彩斑斓的雀鸟栖息在树枝上，甜美地唱着歌。
B2 noun /ˈfaʊn.dər/

Founder

创始人
Meaning
a person who establishes an institution or settlement; someone who starts or creates something
Example
Steve Jobs was the co-founder of Apple Inc. and revolutionized personal computing.
史蒂夫·乔布斯是苹果公司联合创始人，并且革命性地改变了个人计算机。
B1 noun /ˈfɪnɪʃ laɪn/

finish line

终点线
Meaning
The line or point at the end of a race or competition where participants complete it.
Example
She sprinted towards the finish line and won the race.
她冲向终点线并赢得了比赛。
C1 verb /ˈfrɒlɪk/

frolic

欢快地玩耍
Meaning
to play and move about cheerfully, energetically, or playfully
Example
The children frolicked in the garden all afternoon.
孩子们整个下午在花园里欢快地玩耍。
B2 noun /ˈfriːˌlænsər/

freelancer

自由职业者
Meaning
A person who works independently without being permanently employed by one organization.
Example
She works as a freelancer designing websites for different clients.
她作为自由职业者为不同的客户设计网站。
C1 adjective /ˈfræɡməntɪd/

fragmented

碎片化, 分割, 不完整
Meaning
Having been broken into fragments; disjointed or incomplete.
Example
The information was fragmented and difficult to understand.
信息被碎片化了，难以理解。
B1 adverb /ˈfriːkwəntli/

Frequently

频繁; 定期; 多次
Meaning
often; regularly; many times
Example
She frequently visits her grandmother on weekends.
她在周末经常探望她的祖母。
C1 noun /ˈfjuː.dʒə.tɪv/

Fugitive

逃犯
Meaning
a person who has escaped from a place or is in hiding, especially to avoid arrest
Example
The police launched a manhunt to capture the fugitive who escaped from prison.
警方展开了追捕行动，试图抓捕从监狱逃跑的逃犯。
C2 adjective /ˈfæl.oʊ/

fallow

休耕地
Meaning
Describing land that is left unplanted for a period to restore its fertility, allowing soil to recover nutrients and break pest and disease cycles.
Example
Farmers leave their fields fallow to restore soil fertility.
农民将土地休耕，以恢复土壤肥力。
C2 verb /ˌfɔːrˈrʌn/

forerun

预示
Meaning
To go before; to precede in time, place, or action.
Example
Dark clouds often forerun a storm.
乌云常常预示着暴风雨。
A1 noun/verb /fɪlm/

film

电影
Meaning
a motion picture or movie; or to record on camera
Example
They watched a film together on the weekend.
他们在周末一起观看了一部电影。
B1 noun fəˈsɪl.ɪ.tiz

facilities

设施
Meaning
A place, amenity, or piece of equipment provided for a particular purpose.
Example
Facilities improve industrial productivity.
设施提高了工业生产力。
C1 noun ˌfiː.zəˈbɪl.ə.ti

feasibility

可行性
Meaning
The state or degree of being easily or conveniently done; possibility.
Example
The company conducted a feasibility study before launching the project.
公司在启动项目之前进行了可行性研究。
A2 noun /frɒɡ/

Frog

青蛙
Meaning
a small amphibian animal that lives both in water and on land
Example
The frog jumped from the lily pad into the pond.
青蛙从睡莲叶上跳进池塘。
B1 noun /ˌfɜːrst ˈeɪd/

first aid

急救
Meaning
Immediate assistance given to a sick or injured person until full medical treatment is available
Example
He gave first aid to the injured cyclist before the ambulance arrived.
在救护车到来之前，他为受伤的自行车手进行了急救。
B1 adjective /ˈfæsɪneɪtɪŋ/

Fascinating

迷人
Meaning
extremely interesting; captivating; enchanting
Example
The documentary about ocean life was fascinating.
关于海洋生命的纪录片令人着迷。
C2 noun /ˌfoʊ.mənˈteɪ.ʃən/

fomentation

煽动，激起
Meaning
The action of instigating or stirring up; also the application of warm substances to the body to ease pain.
Example
His speech led to the fomentation of violence in the region.
他的演讲导致了该地区暴力的激化。
A1 preposition /fɔːr/

for

为
Meaning
used to indicate purpose, destination, or recipient
Example
This gift is for you.
这个礼物是给你的。
C2 verb /ˈfʊl.mɪ.neɪt/

fulminate

猛烈抗议
Meaning
To express strong protest or criticism loudly and forcefully; to explode violently.
Example
The politician began to fulminate against corruption.
政治家开始猛烈反对腐败。
A2 adjective /ˈfuː.lɪʃ/

Foolish

愚蠢的; 傻的; 可笑的
Meaning
lacking good sense or judgment; unwise; silly
Example
It was foolish of him to drive in such heavy rain.
在这样的暴雨中开车真是愚蠢。
C2 noun /ˈflɪpənsi/

flippancy

轻率
Meaning
lack of seriousness; showing a disrespectful or trivial attitude
Example
His flippancy during the meeting offended his colleagues.
他在会议中的轻率让同事们感到不悦。
C2 adjective /ˈfɛtɪd/

fetid

有恶臭的，令人不快的
Meaning
having a strong, unpleasant smell
Example
The fetid smell from the garbage was unbearable.
垃圾散发出的恶臭让人无法忍受。
C2 adjective /ˈfʊl.səm/

fulsome

过度的赞美
Meaning
Excessively flattering or insincere; abundant or generous in amount.
Example
He offered fulsome praise to his boss.
他给老板提供了过度的赞美。
B2 adverb /ˌfʌndəˈmɛntəli/

fundamentally

从根本上
Meaning
in a basic and important way; at the core
Example
The two theories are fundamentally different.
这两个理论从根本上不同。
B1 verb /floʊt/

float

浮动
Meaning
to rest or move on the surface of a liquid or in the air without sinking
Example
The boat began to float gently down the river.
船开始轻轻漂浮在河面上。
B1 noun /ˌfɜːrst eɪd kɪt/

first aid kit

急救箱
Meaning
A collection of medical supplies for giving initial treatment in emergencies
Example
I always keep a first aid kit in my car for emergencies.
我总是在车里备有急救箱以应对紧急情况。
C1 noun /fiːnd/

fiend

恶魔，邪恶的人
Meaning
an evil spirit or demon; a wicked or cruel person; someone obsessed with a particular thing
Example
He is a real fiend when it comes to solving puzzles.
当涉及解谜时，他真的是个恶魔。
C1 noun /ˈflɔː.rə/

flora

在特定地区或栖息地中发现的植物生命
Meaning
The plant life found in a particular region or habitat.
Example
The Amazon rainforest is home to a vast flora diversity.
亚马逊雨林是丰富的植物群多样性的家园。
C1 noun /ˈfɛərˌɡraʊndz/

fairgrounds

集市场地
Meaning
A designated area where fairs, exhibitions, and amusement events are held
Example
The town set up rides and stalls at the fairgrounds for the annual festival.
小镇在集市场地设置了游乐设施和摊位，为年度节日做准备。
B2 noun /ˈfeð.ər/

Feather

鸟羽毛
Meaning
one of the light structures that cover a bird's body
Example
The peacock has beautiful colorful feathers.
孔雀有美丽的五彩斑斓的羽毛。
C1 verb /ˈflʌtər/

flutter

拍动 / 颤动
Meaning
to move or flap quickly and lightly; to beat or wave with small rapid motions
Example
The butterfly began to flutter its wings in the sunlight.
蝴蝶开始在阳光下扑动它的翅膀。
B2 noun /fluːt/

Flute

长笛
Meaning
a musical wind instrument with holes along its length that is played by blowing across a hole at one end
Example
He played a sweet melody on his flute.
他在他的长笛上演奏了一首甜美的旋律。
C2 noun /ˈfʌstɪən/

fustian

浮夸的演讲
Meaning
pompous or pretentious speech or writing; originally a type of thick cloth
Example
The politician's speech was filled with fustian and empty promises.
政治家的演讲充满了浮夸和空洞的承诺。
C1 noun /frəˈdʒɪl.ɪ.ti/

fragility

脆弱性
Meaning
The quality of being fragile; delicateness.
Example
The cornea's fragility increases with rubbing.
角膜的脆弱性随着摩擦而增加。
B2 adjective /ˈfɜːr.taɪl/

Fertile

肥沃的
Meaning
capable of producing abundant vegetation or crops; able to conceive children
Example
The fertile soil in this region makes it perfect for growing vegetables.
这个地区的肥沃土壤使其成为种植蔬菜的理想之地。
C1 noun /ˈfɔːrˌrʌnər/

forerunner

先驱
Meaning
A person or thing that comes before another; a predecessor or harbinger.
Example
The Wright brothers were the forerunners of modern aviation.
莱特兄弟是现代航空的先驱。
C1 adjective ˈfjuː.taɪl

futile

徒劳的
Meaning
Incapable of producing any useful result; pointless.
Example
His attempts to change the situation were futile.
他改变局势的努力是徒劳的。
A2 noun /fɒks/

Fox

狐狸
Meaning
a wild animal related to dogs, with a pointed face and thick fur
Example
The red fox is known for its cunning nature.
红狐以其狡猾的天性而闻名。
C2 adjective /ˈfraʊzi/

frowsy

邋遢
Meaning
Scruffy and neglected in appearance; musty or stale in smell.
Example
He wore a frowsy old jacket that smelled of damp.
他穿着一件邋遢的旧夹克，散发着潮湿的气味。
C1 noun /ˈfen.jʊ.griːk/

Fenugreek

胡芦巴
Meaning
an herb whose seeds and leaves are used as a spice in cooking
Example
Fenugreek seeds have a slightly bitter taste and are commonly used in Indian cuisine.
胡芦巴种子有轻微的苦味，通常用于印度菜肴中。
C2 noun /ˈfɔːrʃɔːr/

foreshore

海滩
Meaning
The part of the shore between the high and low tide marks
Example
Children were playing on the foreshore, collecting shells.
孩子们在海岸上玩耍，捡贝壳。