a
a — 限定詞
1. you place this word before a noun that labels one individual or object, when you
一個
首次提及單數可數名詞
you place this word before a noun that labels one individual or object, when your listener is encountering that item for the very first time
Ananya bought a bicycle yesterday, but she has not ridden it yet.
Ananya 昨天買了一輛腳踏車,但還沒騎過。
first mention of bicycle
There is a small café on the corner of Park Street.
公園街的轉角有一家小咖啡館。
William found a wallet on the bus this morning.
William 今天早上在公車上找到一個錢包。
A young woman in a red dress walked into the shop and asked for help.
一位身穿紅色連衣裙的年輕女子走進店裡求助。
- some
used in the same position for plural or uncountable nouns, e.g. 'some books' vs 'a book'
- the
used when the listener already knows which one is meant
文法句型
a + singular countable noun
用法筆記
Use 'a' for the first mention of a countable noun. Once the listener knows which item you mean, switch to 'the' for later mentions.
常見錯誤
2. this word comes after verbs like 'be' or 'become' to say which group an individu
一個(類)
表示屬於某個類別
this word comes after verbs like 'be' or 'become' to say which group an individual or object fits into — for instance, what kind of animal, item, or human something is
An octopus is a sea animal with eight long arms.
章魚是一種有八條長觸手的海洋動物。
class membership statement
The Watanabe family owns a small restaurant near the station.
渡邊家在車站附近經營一家小餐館。
Jing's grandmother is a very kind person who helps everyone in the village.
Jing 的祖母是一位非常善良的人,幫助村子裡的每一個人。
This old wooden chair is actually a valuable antique.
這張舊木椅其實是一件珍貴的古董。
- one of
emphasises membership in a larger group, e.g. 'one of the teachers'
文法句型
be + a + noun
become + a + noun
用法筆記
The structure 'subject + be + a + noun' is one of the most basic patterns in English. The noun tells the category; an adjective can be added before it.
常見錯誤
3. you place it in front of the name of someone's job or position when telling a li
一位;一名
用在職業或頭銜前
you place it in front of the name of someone's job or position when telling a listener what work that person does
Elena works as a dentist at the city hospital.
Elena 在市立醫院擔任牙醫。
job role: a + profession
Yuki's father is a police officer in Kyoto.
Yuki 的父親是京都的一名警察。
Thomas trained for three years to become a commercial pilot.
Thomas 受訓三年,成為一名商業飛行員。
Dr. Okafor is a surgeon who works at the teaching hospital in Lagos.
Okafor 醫生是在拉哥斯教學醫院工作的外科醫師。
文法句型
be + a + job title
用法筆記
Always use 'a' or 'an' before a singular job title. Never omit it (❌ 'She is doctor'). If the profession starts with a vowel sound, use 'an' instead: 'an architect', 'an engineer'.
常見錯誤
4. in statements of general truth, it precedes a noun that stands for every member
任何
泛指某一類的所有成員
in statements of general truth, it precedes a noun that stands for every member of that class — 'a cat is a mammal' means all cats are mammals
A cheetah can run much faster than a horse.
獵豹跑得比馬快很多。
generic statement about a species
A good dictionary is an essential tool for any language learner.
一本好字典是任何語言學習者必備的工具。
Arjun believes that a teacher should listen more than they talk.
Arjun 認為老師應該多聽少說。
A bicycle is a cheap and healthy way to travel around the city.
腳踏車是一種在城裡四處移動的便宜又健康的交通方式。
- any
stronger emphasis on 'no matter which', e.g. 'Any dog needs exercise'
文法句型
a + singular noun + verb (general truth)
用法筆記
In formal or academic English, generics can also be expressed with a plural noun without an article ('Cheetahs run fast') or with 'the' ('The cheetah runs fast'). The 'a' form is common in everyday speech.
常見錯誤
5. this replaces the number 'one' when talking about a single object or person, esp
一
代替 one 表示單一個體或物品
this replaces the number 'one' when talking about a single object or person, especially in everyday conversation where the exact count is not the main focus
Raj asked for a glass of water and the waiter brought him two.
Raj 要了一杯水,服務生卻給他兩杯。
a = one, contrasted with two
There is only a single piece of cake left on the plate.
盤子裡只剩下一塊蛋糕。
Neha waited for a whole hour but the bus never came.
Neha 等了整整一個小時,公車卻一直沒來。
The children each took a cookie from the jar and ran outside to play.
每個孩子從餅乾罐裡拿了一塊餅乾,然後跑到外面玩。
- one
stronger emphasis on the number; 'a' is softer and more common in everyday use
文法句型
a + noun (meaning one)
用法筆記
'A' is the usual word for 'one' in everyday speech. Use 'one' instead when you need to emphasise the exact number in contrast to other possibilities ('I want one ticket, not two').
常見錯誤
6. it sits between two units of weight, time, money, or distance to tell you the ra
每
表示比率或每單位
it sits between two units of weight, time, money, or distance to tell you the rate: how much of something happens for each item or period
The train to London runs every hour and costs forty pounds a ticket.
到倫敦的火車每小時一班,每張票四十英鎊。
cost per unit: a ticket
Dewi jogs five kilometres a day in the park near her house.
Dewi 每天在她家附近的公園慢跑五公里。
frequency: a day
Yuki's new car can travel at about fifty kilometres an hour on city roads.
Yuki 的新車在市区道路上一小時大約能開五十公里。
The part-time job pays fifteen dollars an hour with no experience needed.
這份兼職工作時薪十五美元,無需工作經驗。
- per
more formal, e.g. 'per hour', 'per person'
文法句型
number + unit + a + time/money unit
用法筆記
In this sense, 'a' and 'an' are interchangeable with 'per' but sound more natural in spoken English. 'Per' is more formal and common in writing. Use 'an' before vowel sounds: 'an hour', 'an acre'.
常見錯誤
7. it pairs with words that express a strong feeling — including 'what', 'such', 'q
多麼;真
感嘆句中與 what, such 等連用
it pairs with words that express a strong feeling — including 'what', 'such', 'quite' and 'rather' — when a person reacts with wonder, joy, or irritation about something they observe
What a beautiful sunset we saw from the top of the mountain!
我們在山頂上看到了多麼美麗的夕陽啊!
what a + adjective + noun (exclamation)
Noam is such a talented pianist that the audience clapped for five full minutes.
Noam 是一位非常有才華的鋼琴家,觀眾為他鼓掌整整五分鐘。
such a + adjective + noun
The renovation turned out to be quite a big project for such a small team.
對這麼小的團隊來說,這次翻修工程還真是一項大工程。
Jing said it was rather a long walk from the station to her flat.
Jing 說從車站到她公寓的路程相當遠。
文法句型
what + a + adjective + noun!
such + a + adjective + noun
quite + a + noun
用法筆記
The order of words after 'quite' and 'rather' can vary. Both 'quite a big project' and 'a quite big project' are acceptable, though 'quite a' is more common in British English.
常見錯誤
8. you put it in front of a person's name — usually with a title like Mr. or Dr. —
某位
用於不認識的人的姓名前
you put it in front of a person's name — usually with a title like Mr. or Dr. — to tell the listener that you are talking about someone neither of you knows personally
A Mr. Tanaka called while you were out and left his number on the desk.
你外出的時候有一位 Tanaka 先生來電,並在桌上留了電話號碼。
a + title + surname (unknown caller)
The receptionist said that a Dr. Williams was waiting in the lobby to see you.
櫃檯人員說有一位 Williams 醫師在大廳等您。
A young woman named Fatima came by the office asking about the teaching job.
一位名叫 Fatima 的年輕女子到辦公室詢問教職工作。
There is a Professor Kim from Seoul University who wants to meet the dean.
有一位來自首爾大學的 Kim 教授想見院長。
- someone called
less formal, e.g. 'someone called Mr. Tanaka called'
文法句型
a + title + surname
用法筆記
Use this pattern when you are introducing someone the listener does not know. If the listener already knows the person, omit 'a' ('Mr. Tanaka called'). This pattern is slightly formal.
常見錯誤
9. normally you cannot put 'a' in front of uncountable nouns like 'knowledge' or 's
一種
修飾語後用於不可數名詞前
normally you cannot put 'a' in front of uncountable nouns like 'knowledge' or 'silence', but when a describing word or a longer phrase comes between them, it becomes acceptable because you are talking about one special kind or degree
The students showed a deep understanding of the topic after the workshop.
學生們在工作坊後展現出對該主題的深刻理解。
a + adjective + uncountable noun (understanding)
Elena gained a solid knowledge of Japanese after living in Tokyo for three years.
Elena 在東京住了三年後,掌握了扎實的日語知識。
There was a strange silence in the room when the manager announced the news.
經理宣布消息時,房間裡出現了一陣奇怪的寂靜。
Ananya received a good education at the international school in Mumbai.
Ananya 在孟買的國際學校接受了良好的教育。
文法句型
a + adjective + uncountable noun
用法筆記
Normally uncountable nouns (like 'understanding', 'knowledge', 'silence', 'education') do not take 'a'. But when they are modified by an adjective or a 'of'-phrase, 'a' becomes acceptable to show a specific type or degree.
常見錯誤
10. this word appears inside fixed expressions that tell you the amount of something
一些;少量
用於數量詞片語中
this word appears inside fixed expressions that tell you the amount of something, such as 'a few', 'a little', 'a lot of', and 'a great deal of'
Neha invited a few friends over for dinner on Saturday evening.
Neha 邀請了幾位朋友星期六晚上來家裡吃晚餐。
a few + plural noun (small number)
There is only a little milk left in the fridge, not enough for coffee.
冰箱裡只剩下一點牛奶,不夠沖咖啡。
a little + uncountable noun
Thomas spent a lot of money on repairing his old car last month.
Thomas 上個月花了很多錢修理他的舊車。
A large number of people came to the festival despite the heavy rain.
儘管下著大雨,仍有大量民眾前來參加節慶活動。
- some
can replace 'a few' or 'a little' in most contexts
文法句型
a few + plural noun
a little + uncountable noun
a lot of + noun
用法筆記
Be careful with 'few' vs 'a few', and 'little' vs 'a little'. 'A few / a little' means 'some' (positive). 'Few / little' without 'a' means 'not enough' (negative). Compare: 'I have a few friends' (some) vs 'I have few friends' (not enough).
常見錯誤
11. after a negative word such as 'not', 'never', or 'without', this word sits in fr
任何一個
否定句中強調完全沒有
after a negative word such as 'not', 'never', or 'without', this word sits in front of a noun to stress that absolutely nothing of that thing exists
The thief left the house without leaving a single fingerprint behind.
小偷離開房子時,沒有留下任何一個指紋。
without + a + singular noun (zero quantity)
Dewi did not make a single mistake in the entire English exam.
Dewi 在整場英文考試中沒有犯任何一個錯誤。
There was not a cloud in the sky all day long during the beach trip.
沙灘郊遊那天,天空中一整天連一朵雲都沒有。
William has never told a lie to his parents since he was a child.
William 從小到大從未對父母說過一句謊話。
- no
more direct, e.g. 'He made no mistakes' — but 'no' works with both singular and plural
文法句型
not + a + singular noun
never + verb + a + singular noun
用法筆記
Adding 'single' after 'a' ('not a single...') makes the emphasis even stronger. This pattern is common after 'not', 'never', 'without', and 'hardly'.
常見錯誤
12. you put it in front of everyday sicknesses like 'cold', 'headache', 'fever', or
一陣;一場
用於常見疾病名稱前
you put it in front of everyday sicknesses like 'cold', 'headache', 'fever', or 'cough' when telling someone you are feeling unwell or have caught something
Fatima stayed home from school because she had a bad cold and a fever.
Fatima 因為一場重感冒加上發燒,請假沒去上學。
have + a + illness
Arjun went to the pharmacy to get some medicine for a headache.
Arjun 去藥局買頭痛藥。
The doctor told Raj that he had a mild infection and needed rest.
醫生告訴 Raj 他得了輕微的感染,需要休息。
Noam has been off work for three days with a very sore throat.
Noam 因為喉嚨非常痛,已經請假三天沒上班了。
文法句型
have + a + illness
catch + a + illness
get + a + illness
用法筆記
Not all illnesses take 'a'. More serious or scientific disease names often do not: 'cancer', 'diabetes', 'malaria' (no 'a'). The illnesses that take 'a' are generally common, everyday ones: 'a cold', 'a cough', 'a fever', 'a headache', 'a stomach ache'.
常見錯誤
13. you say it in front of number-words including hundred, thousand, million, or doz
一百;一千
用於百、千等數詞前
you say it in front of number-words including hundred, thousand, million, or dozen to signal one of that quantity — used especially when giving round or approximate figures
Ananya saved a hundred dollars by buying the flight tickets early.
Ananya 提早買機票,省了一百美元。
a hundred = one hundred
Over a thousand people attended the music festival in the park last weekend.
上週末有超過一千人參加公園的音樂節。
The company donated a million meals to families in need during the winter.
該公司冬天捐贈了一百萬份餐點給有需要的家庭。
Jing bought a dozen eggs from the market to bake a cake for her niece.
Jing 從市場買了一打雞蛋,為姪女烤蛋糕。
- one
more precise; 'a' is softer and more natural in everyday contexts
文法句型
a hundred/thousand/million/dozen + noun
用法筆記
'A' and 'one' are interchangeable before these numbers, but 'a' is more common in everyday speech. Use 'one' for precise or contrastive counting ('one hundred, not two hundred'). After the first word in a larger number, do not repeat 'a': 'a hundred and twenty-three', not 'a hundred and a twenty-three'.
常見錯誤
14. normally uncountable nouns do not take 'a', but when you want to point out a spe
某種;某款
不可數名詞指特定品種或品質
normally uncountable nouns do not take 'a', but when you want to point out a specific variety, brand, or quality — such as a particular cheese or wine — it becomes correct
The shop sells a very soft cheese that comes from a small farm in France.
這家店賣一種產自法國小農場的非常柔軟的起司。
a + adjective + cheese (specific variety)
Thomas ordered a red wine that the waiter recommended with the lamb dish.
Thomas 點了一杯服務生推薦搭配羊肉料理的紅酒。
There was a kindness in her voice that made everyone feel welcome.
她的聲音裡有一種親切,讓每個人都感到受歡迎。
The artist developed a distinctive beauty in her paintings that critics admired deeply.
這位藝術家在畫作中展現出一種評論家深深讚賞的獨特的美感。
- a kind of
more explicit, e.g. 'a kind of soft cheese'
文法句型
a + uncountable noun (specific type)
用法筆記
This is a more advanced use where normally uncountable nouns (cheese, wine, kindness, beauty) are treated as countable to mean 'a type of' or 'a particular quality of'. Common with foods, materials, and abstract qualities.
常見錯誤
15. you put it in front of a name that has been given an adjective, to highlight a c
一個(新)
修飾語用於專有名詞前
you put it in front of a name that has been given an adjective, to highlight a certain period, version, or set of qualities — for example, a different or new version of a country or artist
After the reforms, the country entered a new China that welcomed foreign investment.
改革之後,該國進入了歡迎外資的新中國時代。
a + adjective + place (new era)
The curator described the sculpture as a very different Picasso from his earlier works.
策展人形容這件雕塑與 Picasso 早期作品截然不同。
Fatima dreamed of building a greener Istanbul with more parks and bike lanes.
Fatima 夢想建造一個擁有更多公園和自行車道的更綠色的伊斯坦堡。
The young pianist was called a modern Mozart by the impressed music critics.
這位年輕的鋼琴家被印象深刻的樂評人譽為現代的莫札特。
文法句型
a + adjective + proper noun
用法筆記
This pattern is common in journalism, literature, and descriptive writing. The adjective before the proper noun highlights specific qualities, periods, or interpretations of that person or place.
常見錯誤
a — 名詞
1. the alphabet's opening letter, written as A or a, and the name of that written s
字母 A
英文字母的第一個字母
the alphabet's opening letter, written as A or a, and the name of that written sign
James traced the capital letter A with his finger while learning to write.
James 學寫字時用手指描摹大寫字母 A。
capital letter A / lowercase a
Anh showed her little brother how to write the letter A in both uppercase and lowercase.
Anh 教她弟弟如何用大寫和小寫書寫字母 A。
collocation: the letter A
The first word in the dictionary was 'a', printed in bold at the top of the page.
字典裡的第一個字是「a」,以粗體印在頁面頂端。
Chidi pointed at the big red letter A on the classroom wall and said the sound out loud.
Chidi 指著教室牆上那個大大的紅色字母 A,大聲唸出它的發音。
文法句型
an A
A's/As (plural) — 'three A's'
用法筆記
When used as a word (the indefinite article), 'a' is a separate grammatical word and not a noun. The noun sense refers to the letter itself as a written symbol or name.
常見錯誤
2. the sixth note in the musical scale of C major; also the name for a key or chord
A 音
C大調音階中的第六個音
the sixth note in the musical scale of C major; also the name for a key or chord based on this note as its starting point
The orchestra tuned their instruments to the note A before the concert began.
音樂會開始前,樂團以 A 音為樂器調音。
collocation: tune to the note A
Luca played an A on the piano and asked his teacher whether the pitch was correct.
Luca 在鋼琴上彈了一個 A 音,問老師音準是否正確。
play + an A + on [instrument]
The violin part for that piece starts on a high A, which is hard for beginners to reach.
那首曲子的小提琴部分從高音 A 開始,對初學者來說很難掌握。
Shira hummed the note A softly while the tuning app on her phone showed a green check mark.
Shira 輕輕哼著 A 音,同時手機上的調音 App 顯示綠色勾號。
文法句型
the note A
an A
in the key of A
用法筆記
Musicians often specify the octave when referring to A, such as 'middle A' (the A near the middle of a piano keyboard, roughly 440 Hz) or 'A above middle C'. The standard tuning frequency for A is 440 Hz.
3. the highest mark given for school work or an examination, meaning that the work
A 等
學校評分中最高的等級
the highest mark given for school work or an examination, meaning that the work is excellent
Theo studied every evening for two weeks and was thrilled to receive an A on his biology exam.
Theo 連續兩週每晚用功讀書,結果生物考試拿到 A 等,興奮不已。
collocation: get/receive an A
Only three students in the whole class earned an A in the final history project.
全班只有三名學生在期末歷史專題中獲得 A。
Hana needed an A in chemistry to keep her scholarship at the university.
Hana 需要在化學科拿到 A 才能保住大學獎學金。
The teacher gave Amir an A for his essay about the water cycle because the diagrams were clear.
老師因為 Amir 的水循環作文圖表清晰,給了他 A。
- F
the lowest passing or failing grade, opposite end of the grading scale
文法句型
an A
get an A
an A in [subject]
an A+ on [assignment]
用法筆記
In many school systems, A is the top grade, followed by B, C, D, and F. Some schools use plus and minus variations (A+, A, A−). An 'A' is different from the indefinite article 'a' — they are spelled the same but are different words.
常見錯誤
a — 縮寫
1. a letter rating used on movies, television shows, video games, or tickets to mea
成人;限制級
電影、遊戲等標示成人專用
a letter rating used on movies, television shows, video games, or tickets to mean suitable for adults only, usually because of mature content
The ticket booth charged an A price for Mateo and a lower price for his younger sister.
售票處對 Mateo 收取成人票價格,對他妹妹則收較低的價格。
A = adult ticket category
Wei could not buy the video game because it had an A rating and he was only fifteen.
Wei 沒辦法買那款電玩,因為它屬於限制級,而他只有十五歲。
Sophie checked the movie poster and saw the A symbol in the corner, meaning the film was for grown-ups only.
Sophie 查看電影海報,看到角落的成人標誌,表示這部電影限成年觀眾觀看。
Omar checked the cinema guide and skipped the film marked A.
Omar 查看電影指南後,跳過了標成 A 的那部片。
文法句型
A = adult
用法筆記
Different rating systems exist across countries; 'A' may mean 'adult' or simply 'adult audience'. Check local classification.
2. a short label written next to a correct response in tests, exercise books, and a
答案
試題或問答中標示解答
a short label written next to a correct response in tests, exercise books, and answer keys, typically enclosed in parentheses or followed by a colon
The back of the maths book had a section labelled "A:" with all the correct answers.
數學課本後面有一個標示「A:」的解答區,列出了所有正確答案。
A: = answer key label
Omar checked his worksheet against the A column to see which problems he got right.
Omar 核對自己學習單上的答案欄,看看哪些題目答對了。
The teacher wrote "A: Paris" next to the question about the capital of France.
老師在關於法國首都的問題旁邊寫了「A:巴黎」。
Élise wrote A beside question three after checking the answer sheet.
Élise 對照答案紙後,在第三題旁邊寫下 A。
- Q
the abbreviation for 'question', appearing opposite 'A' in Q&A format
文法句型
(A) = answer
用法筆記
Very commonly paired with 'Q' (question) in quiz formats: 'Q: What is 2+2? A: 4'. Also used in online forums and customer support transcripts.
3. the letter printed on a playing card to mean the ace, which has a single symbol
A(撲克牌)
撲克牌中代表 ace 的字母
the letter printed on a playing card to mean the ace, which has a single symbol and is either the highest or lowest card depending on the game
Sophie held the A of spades and smiled because it was the highest card in the round.
Sophie 握著黑桃 A 微笑,因為這是該局最大的牌。
A = ace on playing cards
Jing shuffled the deck and dealt an A to each player before explaining the new game rules.
Jing 洗好牌,在解釋新遊戲規則之前給每位玩家發了一張 A。
The poker player placed the A of hearts face down on the table and raised the bet.
那位撲克玩家將紅心 A 牌面朝下放在桌上,然後加注。
Piotr turned over the A of clubs and won the trick.
Piotr 翻開梅花 A,贏下了這墩牌。
文法句型
A = ace
用法筆記
In most card games, 'A' can mean either high or low — check the rules of the specific game. In bridge and poker, it is usually the highest card.
常見錯誤
4. the symbol for the ampere, the standard scientific unit that measures the rate a
安培
電流的標準單位符號
the symbol for the ampere, the standard scientific unit that measures the rate at which electric charge flows through a circuit
The power supply label read "Output: 5 A" meaning it could deliver five amperes of current.
電源供應器標籤上寫著「輸出:5 A」,表示能提供 5 安培的電流。
A = ampere on electrical equipment labels
Budi checked the fuse box and saw that each circuit could handle up to 15 A safely.
Budi 檢查保險絲盒,看到每個電路的安全負載為 15 A。
The science textbook explained that a typical phone charger supplies about one or two A.
科學教科書解釋,一般手機充電器大約提供一到兩安培的電流。
Vivek read 2 A on the charger before plugging in the lamp.
Vivek 插上檯燈前,先看了充電器上標示的 2 A。
文法句型
A = ampere
用法筆記
The capital A is the SI (International System) symbol for ampere. It is written without a period in scientific contexts. Learners may see it on phone chargers, fuses, and power adapters.