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C1 verb/noun ˈfæð.əm

fathom

理解
Meaning
To understand after much thought; to measure the depth of water; to comprehend.
Example
It is difficult to fathom the depths of the ocean.
很难理解海洋的深度。
C1 verb /ˈfɛdərət/

federate

联合
Meaning
to unite in a league or federation; to form an alliance
Example
Several states federated to create a stronger union.
几个州联合起来创造了一个更强大的联盟。
C1 noun/adjective /fɔːrˈboʊdɪŋ/

foreboding

不祥的预感
Meaning
A feeling that something bad will happen; ominous.
Example
She felt a deep sense of foreboding as she entered the abandoned house.
她走进那座废弃的房子时，感到一种深深的不祥预感。
C1 adjective /ˈflɪmzi/

flimsy

脆弱的
Meaning
weak, fragile, or lacking in strength; not convincing
Example
The chair was too flimsy to support his weight.
这把椅子太脆弱了，无法支撑他的重量。
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。
C1 adjective /ˈfɔːrmətɪv/

formative

形成性的
Meaning
Having a lasting influence on a person's development or character.
Example
Childhood is often described as a formative stage in life.
童年常被描述为人生中的一个形成性阶段。
C1 noun ˌfɜːr.tɪ.laɪˈzeɪ.ʃən

fertilization

施肥
Meaning
The process of adding nutrients to soil to increase crop productivity.
Example
Organic fertilization enhances soil health.
有机施肥有助于改善土壤健康。
C1 noun /ˈfoʊk.lɔːr/

folk-lore

民间传说
Meaning
The traditional beliefs, customs, stories, songs, and practices of a community, passed down through generations.
Example
Bangladeshi folk-lore is rich with myths and legends.
中国的民间传说充满了神话和传说。
C1 noun /ˈfaɪər.wɔːl/

firewall

防火墙
Meaning
A network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules.
Example
A firewall protects networks from cyber-attacks.
防火墙保护网络免受网络攻击。
C1 noun ˈfæl.ə.si

fallacy

谬误, 错误的信念, 错误推理
Meaning
False belief, misconception, false reasoning.
Example
The idea that success comes easy is a fallacy.
成功容易到来的这个想法是一个谬误。
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。
C1 verb /fɔːrˈʃædoʊ/

foreshadow

预示
Meaning
To indicate or suggest something that will happen in the future
Example
Dark clouds foreshadowed an approaching storm.
乌云预示着即将来临的暴风雨。
C1 noun /faɪˈnælɪti/

finality

最终性
Meaning
the quality of being final or irreversible; a sense of conclusiveness
Example
The judge's decision gave the case a sense of finality.
法官的决定赋予案件一种最终性的感觉。
C1 noun (plural of fungus) /ˈfʌndʒaɪ/

fungi

真菌
Meaning
a group of spore-producing organisms such as mushrooms, molds, and yeasts
Example
Fungi play an important role in breaking down organic matter in nature.
真菌在自然界中在分解有机物质方面发挥着重要作用。
C1 noun /ˈfoʊliɪdʒ/

foliage

树叶
Meaning
The leaves of a plant, collectively.
Example
The autumn foliage looked stunning in the park.
秋天的树叶在公园里看起来很惊艳。
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。
C1 verb /flɪntʃ/

flinch

退缩
Meaning
to suddenly move back or away due to fear or pain
Example
He didn’t flinch when the doctor gave him the injection.
他在医生给他打针时没有退缩。
C1 verb /feɪn/

feign

假装, 装作
Meaning
to pretend or fake; to give a false appearance of
Example
She feigned illness to avoid going to work.
她假装生病以避免去工作。
C1 adjective /ˈfæn.sɪ.fəl/

fanciful

幻想的, 不现实的
Meaning
overimaginative, unrealistic, or whimsical
Example
The story was too fanciful to be true.
这个故事太幻想了，不可能是真的。
C1 noun, verb /ˈfɛrɪt/

ferret

雪貂, 坚持不懈地寻找或发现某物
Meaning
a small domesticated animal used for hunting; to search or uncover something persistently
Example
He ferreted out the hidden documents.
他发现了隐藏的文件。
C1 noun /ˈfɪʃ.ər/

fissure

裂缝
Meaning
a long, narrow opening or crack in a surface or object
Example
The earthquake caused a deep fissure in the road.
地震在路面上造成了一个深深的裂缝。
C1 noun /foʊ/

foe

敌人
Meaning
an enemy or opponent
Example
The knight fought bravely against his foe.
骑士勇敢地与他的敌人作战。
C1 adjective /ˈfiːzəbl/

feasible

可行的
Meaning
possible to do easily or conveniently; practical and workable
Example
It is feasible to complete the project within two months.
在两个月内完成这个项目是可行的。
C1 verb /fɔːrˈɡoʊ/

forego

放弃
Meaning
to decide not to do or have something pleasant or valuable
Example
She decided to forego dessert to maintain her diet.
她决定放弃甜点，以保持她的饮食。
C1 adjective /fəˈnætɪk/

Fanatic

狂热者
Meaning
extremely passionate about something; showing excessive enthusiasm or devotion
Example
He is a fanatic supporter of his football team.
他是他足球队的狂热支持者。
C1 noun /ˈfeɪvərɪtɪzəm/

favoritism

偏袒
Meaning
the practice of giving unfair preferential treatment to one person or group
Example
The manager was accused of favoritism towards certain employees.
经理被指控偏袒某些员工。
C1 adjective /ˌfɑːrˈfetʃt/

farfetched

不太可能或不太真实
Meaning
unlikely to happen or be true; improbable
Example
His explanation for being late sounded farfetched.
他解释迟到的理由听起来不可信。
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。
C1 adjective /fɪkˈtɪʃəs/

fictitious

虚构的, 假的
Meaning
not real or true; imaginary or fabricated
Example
The story he told was entirely fictitious.
他讲的故事完全是虚构的。
C1 verb /ˈfɔːrfɪt/

forfeit

Meaning
to lose or give up something, usually as a penalty for wrongdoing
Example
He had to forfeit the match after breaking the rules.
C1 adjective /ˈfeɪt.fəl/

fateful

决定性或灾难性的
Meaning
having significant or disastrous consequences
Example
Their fateful decision changed the course of history.
他们的决定性决定改变了历史的进程。
C1 verb /ˈfɪdʒɪt/

fidget

坐立不安，焦虑不安
Meaning
to make small movements, especially because of nervousness or impatience
Example
The child began to fidget during the long lecture.
孩子在漫长的讲座中开始不停地动。
C1 adjective /ˈfrɔːdjʊlənt/

fraudulent

欺诈的
Meaning
Involving or using deceit, especially criminal deception.
Example
He was arrested for making fraudulent insurance claims.
他因提交欺诈性保险索赔而被捕。
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。
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。
C1 noun /ˈfæk.ʃən/

Faction

派系
Meaning
a small organized dissenting group within a larger one
Example
Different factions within the party disagreed about the new policy.
党内的不同派系对新政策存在分歧。
C1 adjective /ˈfrɪdʒɪd/

Frigid

寒冷的; 冰冻的
Meaning
extremely cold; freezing; icy
Example
The frigid weather made it difficult to go outside.
寒冷的天气让出去变得困难。
C1 noun /fæd/

fad

短暂流行的时尚，趋势
Meaning
a temporary fashion or trend; a short-lived craze
Example
The new diet became a popular fad among teenagers.
新的饮食成了青少年中的短暂流行趋势。
C1 noun /ˈfænsiər/

fancier

爱好者
Meaning
a person who has a special interest in a particular thing or activity, especially animals or hobbies
Example
He is a fancier of rare birds.
他是稀有鸟类的爱好者。
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。
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。
C1 noun/verb /fliːs/

fleece

Meaning
The woolly covering of a sheep; as a verb, to swindle or cheat someone.
Example
The farmer sheared the sheep’s fleece carefully.
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！
C1 noun /ˈfʊtˌnoʊt/

foot-note

脚注
Meaning
A note of reference, explanation, or comment placed at the bottom of a page.
Example
The author included a foot-note to explain the historical context.
作者加入了一个脚注，以解释历史背景。
C1 noun /ˈfæm.ɪn/

Famine

饥荒
Meaning
extreme scarcity of food; a period when food is extremely scarce
Example
The severe drought led to widespread famine in the region.
严重的干旱导致该地区广泛的饥荒。
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。
C1 noun /fɪˈnænʃɪər/

financier

金融家
Meaning
a person who manages large amounts of money or investments
Example
The financier advised the company on its investments.
金融家为公司提供了关于投资的建议。
C1 adjective /fərˈlɔːrn/

forlorn

孤独的, 绝望的
Meaning
extremely sad, lonely, or abandoned
Example
The abandoned puppy looked so forlorn in the rain.
被遗弃的小狗在雨中看起来如此悲伤。
C1 noun ˈfɜːr.vɚ

fervor

热情或热衷
Meaning
Strong passion or enthusiasm for something.
Example
He spoke with great fervor about his vision for the company.
他以极大的热情谈论他对公司未来的愿景。
C1 noun /ˈfɔːrdʒər/

forger

伪造者
Meaning
a person who makes fake documents, artworks, or signatures
Example
The police arrested a forger who had been selling counterfeit paintings.
警方逮捕了一名伪造者，他一直在出售伪造的画作。
C1 adjective /ˈfɪɡərətɪv/

figurative

比喻的
Meaning
not literal; using figures of speech or symbolic representation
Example
She used figurative language to describe her feelings.
她用比喻的语言来描述她的感受。
C1 verb /fɔrˈstɔl/

forestall

提前预防
Meaning
to prevent by acting in advance; to anticipate and counter
Example
They forestalled the crisis by taking immediate action.
他们通过立即行动避免了危机。
C1 noun /fɪlθ/

filth

肮脏
Meaning
dirty or disgusting matter; moral corruption
Example
The streets were full of filth after the storm.
暴风雨后街道上满是肮脏。
C1 adjective /ˈflæɡɪŋ/

flagging

变得疲惫、虚弱或失去热情
Meaning
becoming tired, weaker, or less enthusiastic
Example
After hours of work, his energy was flagging.
经过数小时的工作，他的精力正在减退。
C1 adjective /ˈfɔːrsəbl/

forcible

强行
Meaning
Done by force; using physical strength or power.
Example
The police made a forcible entry into the house.
警方强行进入了房屋。
C1 adjective /ˈfænsiːd/

fancied

想象的, 渴望的
Meaning
imagined, desired, or believed without evidence
Example
He is a fancied suitor in the eyes of the young lady.
他是年轻女士眼中的一位想象中的追求者。
C1 noun /ˈfɔːrmən/

foreman

负责一组工人的人，特别是在工厂或建筑工地上
Meaning
a person in charge of a group of workers, especially in a factory or construction site
Example
The foreman supervised the workers on the construction site.
工头在建筑工地上监督工人。
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 adjective /ˈfɑːð.ər.ləs/

fatherless

没有父亲
Meaning
without a father
Example
The fatherless child relied on the support of his community.
这个没有父亲的孩子依赖于他社区的支持。
C1 noun /flʌks/

flux

流动
Meaning
continuous change or movement; the rate of flow of something
Example
The company was in a state of constant flux during the reorganization.
公司在重组期间处于持续变化的状态。
C1 noun /ˈfren.zi/

Frenzy

狂热
Meaning
a state or period of uncontrolled excitement or wild behavior; intense activity
Example
The announcement of the sale created a shopping frenzy at the mall.
销售公告在商场引发了一场购物狂潮。
C1 noun /fəˈtæləti/

fatality

致命事故
Meaning
An occurrence of death by accident, disaster, or violence.
Example
The accident resulted in one fatality.
这场事故导致了一人死亡。
C1 noun /flæt fɪʃ/

Flat fish

比目鱼
Meaning
a type of fish with a flattened body that lives on the sea floor
Example
Flat fish like sole and flounder are excellent for grilling.
像鳎鱼和比目鱼这样的平鱼非常适合烤制。
C1 noun /ˌfɪɡjʊˈriːn/

figurine

小型装饰雕像
Meaning
a small ornamental statue or model of a human or animal
Example
She bought a porcelain figurine of a dancing ballerina.
她买了一尊舞蹈芭蕾舞者的瓷雕像。
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。
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。
C1 noun/verb /ˈfʌrəʊ/

furrow

Meaning
A long narrow trench made in the ground by a plow; to make wrinkles or grooves.
Example
The farmer plowed furrows in the field.
C1 adjective /frɔːt/

fraught

充满
Meaning
Filled with or likely to result in something undesirable.
Example
The negotiations were fraught with tension and uncertainty.
谈判充满了紧张和不确定性。
C1 adjective /ˈfaɪ.naɪt/

Finite

有限的; 有边界的
Meaning
limited; having bounds or limits; not infinite
Example
Earth has finite natural resources.
地球有有限的自然资源。
C1 noun/verb /freɪ/

fray

争斗, 磨损
Meaning
As a noun, a fight or heated dispute; as a verb, to unravel or wear out through friction.
Example
He tried to stay calm, but his nerves began to fray during the argument.
他试图保持冷静，但在争论中他的神经开始磨损。
C1 noun /fɪˈnɑːleɪ/

finale

结尾
Meaning
the last part or conclusion of a performance, event, or series
Example
The concert ended with a spectacular finale.
音乐会以一个壮观的菲纳尔结束。
C1 adjective ˈflʌd proʊn

flood-prone

易受洪水影响
Meaning
Susceptible to flooding; likely to experience floods frequently.
Example
Bangladesh is a flood-prone deltaic nation.
孟加拉国是一个容易发生洪水的三角洲国家。
C1 noun /fɑːrs/

farce

闹剧
Meaning
a comic dramatic work using buffoonery and horseplay, or a ridiculous situation
Example
The meeting turned into a complete farce with everyone arguing.
会议变成了一场彻底的闹剧，大家都在争论。
C1 noun ˌflʌk.tʃuˈeɪ.ʃən

fluctuation

波动
Meaning
An irregular rising and falling in number or amount; a variation.
Example
The stock market experiences frequent fluctuation.
股市经常经历波动。
C1 adjective /ˈfeɪl.seɪf/

fail-safe

故障保护
Meaning
designed to prevent failure or accidents; guaranteed to work correctly
Example
The engineers installed a fail-safe mechanism in the nuclear plant.
工程师在核电厂安装了故障保护机制。
C1 noun /ˈfræk.tʃər/

Fracture

骨折; 骨裂
Meaning
the cracking or breaking of a hard object or material; a break in a bone
Example
The doctor confirmed that he had a hairline fracture in his wrist.
医生确认他在手腕上有一条细小的骨折。
C1 adjective /ˈflæʃi/

flashy

华丽的，炫耀的
Meaning
ostentatious or showy in a way that attracts attention
Example
He drove a flashy sports car through the city streets.
他开着一辆华丽的跑车穿过城市街道。
C1 verb /ˈfɜːrmɛnt/

ferment

经历一个化学过程，其中糖分转化为酒精或酸; 激起或引发变化
Meaning
to undergo a chemical process where sugars are converted to alcohol or acid; to incite or stir up change
Example
The grapes are left to ferment for several weeks.
葡萄被留下来发酵几个星期。
C1 noun /ˈfjʊərɔːr/

furor

骚动
Meaning
An outbreak of public anger or excitement.
Example
The politician's remarks created a furor in the media.
政治家的言论在媒体上引发了一场轰动。
C1 noun /ˈfɔːr.tɪ.tjuːd/

fortitude

坚韧
Meaning
Courage in pain or adversity; mental and emotional strength in facing difficulty.
Example
She faced adversity with great fortitude.
她以巨大的勇气面对困境。
C1 verb /ˈfʌmbəl/

fumble

搞乱
Meaning
to handle something clumsily or to make mistakes while doing something
Example
He fumbled with the keys and dropped them on the floor.
他搞乱了钥匙，把它们掉在地板上。
C1 noun /fəˈnætɪsɪzəm/

fanaticism

狂热
Meaning
the quality of being fanatical; extreme zeal or obsession
Example
Religious fanaticism can lead to intolerance and conflict.
宗教狂热可能导致不宽容和冲突。
C1 noun /ˈfɔːrsəm/

foursome

四人组
Meaning
a group of four people or things, especially in games or social activities
Example
The foursome enjoyed a game of golf together.
四人组一起享受了一场高尔夫比赛。
C1 verb /fret/

fret

担心
Meaning
to worry or be anxious; to be troubled
Example
Don't fret about the exam results.
不要为考试成绩而烦恼。
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。
C1 noun, verb /ˈfrænʧaɪz/

franchise

特许经营
Meaning
A legal right to sell or distribute goods or services in a specific area; to grant such a right.
Example
He opened a new fast-food franchise in the city.
他在城市里开设了一家新的快餐特许经营店。
C1 adjective /ˈflaʊəri/

flowery

花哨的 / 装饰的
Meaning
Full of flowers or overly elaborate in style or language.
Example
She wrote a flowery letter filled with poetic phrases.
她写了一封充满诗意的花哨信。
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。
C1 adjective /ˈfɜːr.vənt/

fervent

热情的，激情四射的
Meaning
having or showing intense passion or enthusiasm
Example
She gave a fervent speech about climate change.
她发表了关于气候变化的热情演讲。
C1 adjective /ˈfliː.tɪŋ/

fleeting

短暂的
Meaning
Lasting for a very short time; passing quickly.
Example
Happiness can be fleeting, so cherish every moment.
幸福可能是短暂的，所以珍惜每一刻。
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 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 /fjuːd/

feud

争吵, 仇恨
Meaning
a prolonged and bitter quarrel or conflict, often between families or groups
Example
The two families have been in a feud for generations.
这两个家庭已经世代争斗。
C1 adjective /ˈfruːt.ləs/

Fruitless

徒劳的; 无用的; 无效的;
Meaning
unsuccessful; futile; pointless;
Example
After hours of searching, their efforts proved fruitless.
经过数小时的搜索，他们的努力证明是徒劳的。
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。
C1 noun /fiːt/

feat

壮举
Meaning
an achievement that requires great courage, skill, or strength
Example
Climbing Mount Everest was a remarkable feat.
攀登珠穆朗玛峰是一项非凡的壮举。
C1 noun /ˈfɔːr.teɪ/ or /fɔːrt/

forte

强项
Meaning
a strong ability or talent; something one does particularly well
Example
Cooking is definitely her forte.
做饭绝对是她的强项。
C1 adjective /frəˈtɜːrnəl/

fraternal

Meaning
Relating to brothers or brotherhood; friendly and supportive.
Example
The two nations maintain a fraternal relationship.
C1 noun ˈfɔː.saɪt

foresight

远见
Meaning
The ability to predict or the action of predicting what will happen or be needed in the future.
Example
His foresight helped the company avoid financial losses.
他的远见帮助公司避免了经济损失。
C1 noun /ˈfɔːrˌbɛər/

forebear

祖先
Meaning
An ancestor, especially one who lived a long time ago.
Example
He often speaks of his forebears with great respect.
他常常带着极大的敬意谈论他的祖先。
C1 adjective /ˈfjuː.dəl/

feudal

封建的
Meaning
relating to the system of feudalism, a medieval social system based on land ownership and obligations
Example
The castle is a remnant of the feudal era.
城堡是封建时代的遗迹。
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 adjective /ˈfleɪɡrənt/

flagrant

显眼且明显错误
Meaning
shockingly noticeable or evident; glaringly wrong
Example
It was a flagrant violation of the rules.
这是对规则的明显违反。
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。
C1 adjective ˈfɔːr.mɪ.də.bəl

formidable

强大的
Meaning
Inspiring fear or respect through being impressively large, powerful, intense, or capable.
Example
The boxer was a formidable opponent in the ring.
那名拳击手是拳台上一个强大的对手。
C1 verb /ˈfɔːrtɪˌfaɪ/

fortify

加强
Meaning
To strengthen a place, person, or thing physically or mentally.
Example
They fortified the city walls to protect against invasion.
他们加固了城市的墙壁，以防止入侵。
C1 noun /fɔːrˈmæl.ə.ti/

Formality

形式
Meaning
the rigid observance of rules of convention or etiquette; a thing done simply to comply with requirements
Example
The signing of the contract was just a formality; the deal was already agreed upon.
签署合同只是一个形式；交易已经达成。
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。
C1 verb, noun /ˈflʌstər/

fluster

使困惑
Meaning
to make someone agitated or confused
Example
The unexpected question flustered him.
这个意外的问题让他感到困惑。
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。
C1 noun, verb /ˈfɜːrloʊ/

furlough

临时休假
Meaning
temporary leave of absence from work, especially that granted to an employee or soldier
Example
Many workers were placed on furlough during the crisis.
许多工人在危机期间被放置在休假状态。
C1 noun ˈflɔː.rə ænd ˈfɔː.nə

flora and fauna

植物和动物
Meaning
The plants and animals of a particular region, habitat, or geological period.
Example
The Galápagos Islands have unique flora and fauna.
加拉帕戈斯群岛拥有独特的植物和动物。
C1 adjective /ˈfɔːrθˌraɪt/

forthright

直率
Meaning
Direct and honest in speech or behavior; straightforward.
Example
She was forthright in her criticism of the policy.
她在批评政策时非常直率。
C1 adjective /ˈfruː.ɡəl/

Frugal

节俭; 经济
Meaning
economical; thrifty;
Example
She is very frugal and saves money by buying only necessary items.
她非常节俭，通过只购买必要的物品来节省钱。
C1 adjective /ˈfɜːrtɪv/

furtive

秘密的
Meaning
Attempting to avoid notice or attention, typically because of guilt or a belief that discovery would lead to trouble.
Example
He cast a furtive glance at the door before leaving.
他在离开前悄悄地看了一眼门。
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。
C1 adjective ˈfæʃ.ɪst

fascist

法西斯
Meaning
Relating to or characteristic of fascism; extremely authoritarian.
Example
Fascist governance undermines freedom.
法西斯统治破坏自由。
C1 adjective /ˈfiːbl/

feeble

虚弱, 软弱
Meaning
lacking physical strength or vigor; weak
Example
After the illness, she felt too feeble to stand.
生病后，她感到太虚弱无法站立。
C1 noun /frɪndʒ/

fringe

装饰边缘 / 边界
Meaning
A decorative border of threads; the outer edge or margin of something.
Example
The festival had a fringe of small independent performances.
节日有一条小型独立表演的边缘。
C1 verb /fɔːrˈseɪk/

forsake

Meaning
to abandon or give up something or someone
Example
He decided not to forsake his old friends despite his success.
C1 adjective /ˈflʌstərd/

flustered

困惑
Meaning
in a state of confusion or agitation
Example
She appeared flustered after being asked so many questions.
她在被问了那么多问题后，看起来有些困惑。