In English, numbers are used to count, label, measure, and talk about time, dates, prices, and quantities. You will use cardinal numbers for counting, ordinal numbers for order, and common number patterns for large values, decimals, and fractions. This module focuses on the forms you need to say, read, and write numbers naturally in everyday contexts.

Cardinal numbers answer “How many?” and are used for counting and quantities. English forms are built from basic numbers 0–19, tens like 20, 30, 40, and combinations like 21, 57, 99. For numbers 21–99 that are not exact tens, use a hyphen in writing: twenty-one, sixty-five. Use “and” only in specific styles, especially British usage for 101+ in some contexts.

Word/Phrase	🇨🇳 中文 单词/短语	Definition	🇨🇳 中文 定义	Example	🇨🇳 中文 示例
zero	🔢 零	Number 0	数字 0	I have zero messages.	🗣️ 我没有消息。
one	🔢 一	Number 1	数字 1	One ticket, please.	🗣️ 请给我一张票。
two	🔢 二	Number 2	数字 2	Two coffees, please.	🗣️ 请来两杯咖啡。
ten	🔢 十	Number 10	数字 10	It costs ten dollars.	🗣️ 它要花十美元。
eleven	🔢 十一	Number 11	数字 11	Eleven people came.	🗣️ 来了十一人。
twenty	🔢 二十	Number 20	数字 20	We waited twenty minutes.	🗣️ 我们等了二十分钟。
forty	🔢 四十	Number 40	数字 40	She is forty years old.	🗣️ 她四十岁。
hundred	🔢 百	100	100	A hundred pages.	🗣️ 一百页。
thousand	🔢 千	1,000	1,000	Two thousand residents.	🗣️ 两千名居民。
million	🔢 百万	1,000,000	1,000,000	A million views.	🗣️ 一百万次观看。

Ordinal numbers answer “Which one?” and show order, position, or sequence. Most ordinals add -th, but some are irregular: first, second, third. In writing, you often see 1st, 2nd, 3rd, 4th. Ordinals are common with dates, floors, rankings, and steps in instructions.

Word/Phrase	🇨🇳 中文 单词/短语	Definition	🇨🇳 中文 定义	Example	🇨🇳 中文 示例
first	🥇 第一个	Position 1	位置 1	This is my first day.	🗣️ 这是我的第一天。
second	🥈 第二个	Position 2	位置 2	Take the second left.	🗣️ 走到第二个左转。
third	🥉 第三个	Position 3	位置 3	He finished third.	🗣️ 他排在第三。
fourth	🔢 第四个	Position 4	位置 4	The fourth chapter is short.	🗣️ 第四章很短。
fifth	🔢 第五个	Position 5	位置 5	It’s on the fifth floor.	🗣️ 它在五楼。
21st	📅 第21个	Ordinal for 21	21 的序数形式	My birthday is on the 21st.	🗣️ 我的生日在二十一日。

For large numbers, English groups digits in threes: thousand, million, billion. In most English writing, use commas as separators: 1,000; 25,000; 3,500,000. When saying large numbers, you can break them into chunks: three million five hundred thousand. “A hundred” and “a thousand” are common in speech, but the exact number is used in formal contexts.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Use thousand, million, billion for 10³, 10⁶, 10⁹	📏 使用 thousand、million、billion 表示 10³、10⁶、10⁹	2,000,000 is two million.	🗣️ 2,000,000 是两百万。
Say numbers in grouped chunks	🧱 将数字按分组的块来读	350,420 is three hundred fifty thousand four hundred twenty.	🗣️ 350,420 是三十五万零四百二十。
Use commas in standard number formatting	🧾 在标准数字格式中使用逗号	The population is 1,250,000.	🗣️ 人口是 1,250,000。
Use a before hundred and thousand in casual speech	🗣️ 在口语中，百和千前会有 a（如 a hundred）	It’s a hundred miles away.	🗣️ 离这里有一百英里。

Fractions describe parts of a whole and are common in recipes, measurements, and everyday quantities. Use “a” for one when speaking: a half, a quarter. Pluralize the denominator when the numerator is greater than one: two thirds, three quarters. For mixed numbers, say the whole number then the fraction: two and a half.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Use a for common fractions	🍰 使用 a 表示常见分数	I’ll have a half.	🗣️ 我想要一半。
Use plural denominators for numerators over one	🍰 当分子大于1时，分母使用复数	Two thirds of the class agreed.	🗣️ 全班有三分之二同意。
Say mixed numbers with and	🍰 将带分数读作整数与分数，用 and 连接	It’s two and a half hours.	🗣️ 它是两小时半。
Quarter is common for one fourth	🍰 对于 one fourth，quarter 很常见	Add a quarter cup of milk.	🗣️ 加四分之一杯牛奶。

Decimals are used for prices, measurements, and precise values. Say the decimal point as “point,” then read digits individually: 3.14 is three point one four. For money, you often say the amount in dollars and cents: $2.50 is two dollars and fifty cents, or two fifty in informal speech. Leading zeros are spoken: 0.5 is zero point five.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Say point for the decimal symbol	📍 将小数点读作 point	4.6 is four point six.	🗣️ 4.6 是四点六。
Read digits after the point one by one	🔢 逐位读出小数点后的数字	7.03 is seven point zero three.	🗣️ 7.03 是七点零三。
For prices, use dollars and cents or a short form	💵 在价格中，使用美元和美分或简写形式	$3.75 is three dollars and seventy-five cents.	🗣️ $3.75 是三美元和七十五美分。
0️⃣ Say zero before the point when needed	0️⃣ 需要时在小数点前读出零	0.8 is zero point eight.	🗣️ 0.8 是零点八。

To tell time in English, you can use a digital style with hours and minutes or a conversational style with past and to. For exact times, say the hour then the minutes: nine fifteen, six forty. Use o’clock for exact hours: five o’clock. Use a.m. for times from midnight to before noon, and p.m. for times from noon to before midnight.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Say hour then minutes for most times	🕒 先说小时再说分钟，大多数时间用	It’s 8:20. It’s eight twenty.	🗣️ 它是 8:20。它是八点二十分。
Use o’clock only for exact hours	🕔 仅在整点时使用 o’clock	It’s 3:00. It’s three o’clock.	🗣️ 它是 3:00。它是三点整。
Use a.m. for morning times	🌅 早上时间用 a.m.	The meeting is at 9 a.m.	🗣️ 会议在 9 a.m.。
Use p.m. for afternoon and evening times	🌙 下午和晚上时间用 p.m.	Dinner is at 7 p.m.	🗣️ 晚餐在 7 p.m.。

A common conversational way to tell time uses past for minutes after the hour and to for minutes before the next hour. Use quarter past for :15 and half past for :30. For :45, you often say quarter to the next hour. This style is frequent in British English and also understood widely in other varieties.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Use past for minutes 1–30 after the hour	⏱️ 小时后 1–30 分钟用 past	6:10 is ten past six.	🗣️ 6:10 是六点十分。
Use to for minutes 31–59 before the next hour	⏱️ 下一小时前的 31–59 分钟用 to	6:50 is ten to seven.	🗣️ 6:50 是六点差十分钟到七点。
Use quarter past for :15	🧩 对于 :15 使用 quarter past	2:15 is quarter past two.	🗣️ 2:15 是两点一刻。
Use half past for :30	🧩 对于 :30 使用 half past	9:30 is half past nine.	🗣️ 9:30 是九点半。
Use quarter to for :45	🧩 对于 :45 使用 quarter to	4:45 is quarter to five.	🗣️ 4:45 是四点差一刻到五点。

Time phrases locate events relative to now and help you schedule naturally. Use at for clock times, on for days and dates, and in for months, years, and longer periods. Use expressions like in the morning, at night, and on the weekend depending on variety. These patterns connect numbers to real-life time and make your speech sound natural and precise.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Use at for clock times	📍 Use at for clock times	The train leaves at 6:45.	🗣️ The train leaves at 6:45.
Use on for days and dates	📅 Use on for days and dates	It’s on Monday. It’s on April 10.	🗣️ It’s on Monday. It’s on April 10.
Use in for months, years, and seasons	🗓️ Use in for months, years, and seasons	We met in 2022.	🗣️ We met in 2022.
Use in the morning, in the afternoon, in the evening	🌤️ Use in the morning, in the afternoon, in the evening	I work in the morning.	🗣️ I work in the morning.
Use at night	🌙 Use at night	It’s quiet at night.	🗣️ It’s quiet at night.

Use cardinal numbers for counting and quantities and ordinal numbers for order, floors, and dates. Build large numbers with thousand, million, and billion, and read them in chunks. Say fractions and decimals with consistent spoken patterns, especially point for decimals. For time, use hour-minute style or the past and to style, and combine times with at, on, and in to place events correctly.