Addition is the math operation used to combine two or more numbers to get a total. In English, we talk about the numbers being combined and the result of combining them. The central idea is that addition increases a total by putting amounts together.

In English, the plus sign + is read as plus, and the equals sign = is read as equals. You will also see addition written in words, especially in instructions or word problems. Being able to read both symbol form and word form helps you understand math in everyday English.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Read + as plus	➕ 将 + 读作 'plus'	3 + 2 equals 5	➕ 3 + 2 等于 5
Read = as equals	🟰 将 = 读作 'equals'	10 + 4 = 14	🟰 10 + 4 = 14
Use plus between numbers in writing	✍️ 在书写时在数字之间使用 '+'	6 plus 7 is 13	✍️ 6 加 7 等于 13
In word problems, addition may be implied	🧾 在文字题中，可能隐含加法	You have 2 apples and get 3 more	🧾 你有 2 个苹果，再得到 3 个

English has specific vocabulary for the parts of an addition problem. Knowing these terms helps you follow explanations, textbooks, and teacher instructions. Some terms are common in school, while others are used in daily life.

Word/Phrase	🇨🇳 中文 词/短语	Definition	🇨🇳 中文 定义	Example	🇨🇳 中文 示例
add	➕ add	put numbers together to find a total	➕ 把数字放在一起以求总和	Add 4 and 9	➕ 将 4 与 9 相加
addition	🧮 addition	the operation of adding	🧮 相加的运算	Addition is used to find the total	🧮 加法用于求总和
sum	🔢 sum	the result of adding	🔢 相加的结果	The sum of 8 and 5 is 13	🔢 8 与 5 的和是 13
addend	🧩 addend	a number being added	🧩 被加的数	In 6 + 1, both numbers are addends	🧩 在 6 + 1 中，两个数都是加数
total	📈 total	the final amount after adding	📈 加法后的最终数量	The total is 27	📈 总数是 27
increase	📊 increase	to make a number bigger by adding	📊 通过相加使数字变大	Increase 20 by 3	📊 将 20 增加 3

Addition equations can be read in several natural English patterns. You can say the numbers first, or you can name the operation and then the numbers. These different readings mean the same thing, but some are more common in school and some in conversation.

Word/Phrase	🇨🇳 中文 词/短语	Definition	🇨🇳 中文 定义	Example	🇨🇳 中文 示例
A plus B equals C	🗣️ A plus B equals C	standard way to read an equation	🗣️ 朗读方程的标准方式	9 plus 1 equals 10	🗣️ 9 plus 1 equals 10
A plus B is C	🗣️ A plus B is C	shorter spoken form of equals	🗣️ 等号的简短口语形式	12 plus 8 is 20	🗣️ 12 plus 8 is 20
The sum of A and B is C	🗣️ The sum of A and B is C	formal phrasing using sum	🗣️ 使用和的正式表达	The sum of 3 and 4 is 7	🗣️ The sum of 3 and 4 is 7
Add A and B	🗣️ Add A and B	instruction form	🗣️ 指示形式	Add 15 and 6	🗣️ Add 15 and 6
A added to B	🗣️ A added to B	phrasing that means A + B	🗣️ 表示 A + B 的措辞	5 added to 9 is 14	🗣️ 5 added to 9 is 14

In English word problems, addition is often signaled by specific verbs and phrases. These cues usually mean you are combining amounts or finding a total. Understanding the language helps you choose addition even when the plus sign is not shown.

Word/Phrase	🇨🇳 中文 词/短语	Definition	🇨🇳 中文 定义	Example	🇨🇳 中文 示例
altogether	🧾 altogether	in total when combining groups	🧾 将组内元素合并后得到的总计	How many apples are there altogether	🧾 一共有多少个苹果
in total	🧾 in total	the final combined amount	🧾 最终合并后的数量	In total, you have 12	🧾 总共，你有 12
combined	🧾 combined	put together as one amount	🧾 作为一个总量放在一起	Combined, they weigh 9 kilograms	🧾 Combined, they weigh 9 kilograms
plus	🧾 plus	add one amount to another	🧾 将一个量加到另一个量	The cost is 30 plus tax	🧾 The cost is 30 plus tax
more	🧾 more	an additional amount	🧾 额外数量	You get 2 more points	🧾 You get 2 more points
together	🧾 together	as one group or total	🧾 作为一个组或总数	Count them together	🧾 Count them together

Add is usually used as a verb for an action or instruction, while plus is often used as an operator between numbers. Both relate to addition, but they appear in different sentence patterns. Choosing the right one makes your math English sound natural.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Use add for instructions or actions	🧮 使用 add 表示指令或动作	Add 3 to 10	🧮 将 3 加到 10
Use plus between numbers in an expression	➕ 在表达式中的数字之间使用 plus	10 plus 3 is 13	➕ 10 plus 3 is 13
Use add up to talk about finding a total	🗣️ 使用 add up 来谈论求和	These numbers add up to 50	🗣️ 这些数字相加得到 50
Use plus for extra features in everyday English	🧾 在日常英语中使用 plus 表示额外特征	The job includes health insurance plus a bonus	🧾 The job includes health insurance plus a bonus

Addition is often described using change language like increase, raise, and go up. This language focuses on how a value changes rather than how two numbers are written. It is common in money, prices, scores, and statistics.

Word/Phrase	🇨🇳 中文 词/短语	Definition	🇨🇳 中文 定义	Example	🇨🇳 中文 示例
increase by	📈 increase by	add a specific amount	📈 增加一个特定数量	Increase the price by 5 dollars	📈 将价格提高 5 美元
increase to	📈 increase to	reach a new total after adding	📈 相加后达到的新总额	The price increased to 50 dollars	📈 价格上升到 50 美元
go up by	⬆️ go up by	informal way to say increase by	⬆️ 增加的非正式说法	The score went up by 2	⬆️ 得分上涨了 2
rise by	⬆️ rise by	formal way to say increase by	⬆️ 正式说法	Sales rose by 10 percent	⬆️ 销售额上升了 10%
add on	➕ add on	include an extra amount	➕ 包含额外金额	Add on a service fee	➕ 增加一项服务费

In English, addition is often paired with estimation when you do not need an exact sum. People use rounding language and approximation phrases to talk about totals quickly. This is common in shopping, time planning, and rough calculations.

Word/Phrase	🇨🇳 中文 词/短语	Definition	🇨🇳 中文 定义	Example	🇨🇳 中文 示例
≈ about	≈ about	≈ not exact, close to the real total	≈ 不精确，接近真实总数	≈ It is about 100 in total	≈ 总数大约是 100
≈ around	≈ around	≈ approximately	≈ 大约	≈ Around 30 people came	≈ 大约有 30 个人到来
≈ roughly	≈ roughly	≈ approximate, often more formal	≈ 近似，通常更正式	≈ Roughly 250 dollars altogether	≈ 大致总共 250 美元
round up	🔁 round up	make a number higher to estimate	🔁 向上取整以进行估算	Round up to 20	🔁 Round up to 20
round down	🔁 round down	make a number lower to estimate	🔁 向下取整以进行估算	Round down to 50	🔁 Round down to 50

Addition can appear in different written formats in English materials, including horizontal and vertical layouts. You may also see numbers written as words in early learning or in checks and documents. Recognizing the same operation across formats improves reading confidence.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Horizontal form is common in text	➡️ 水平形式在文本中很常见	14 + 6 = 20	➡️ 14 + 6 = 20
Vertical form is common in worksheets	⬇️ 垂直形式在工作表中很常见	14	⬇️ 14 + 6 = 20
Numbers may be written as words	🔤 数字也可写成单词	Four plus six equals ten	🔤 Four plus six equals ten
Money and totals often use currency symbols	🧾 金钱和总数常使用货币符号	5 dollars + 2 dollars = 7 dollars	🧾 5 dollars + 2 dollars = 7 dollars

This module taught the essential English vocabulary and phrasing for addition: the meaning, symbols, key terms, common ways to read equations, and typical word-problem cues. You can now recognize addition language in school math and everyday contexts like prices, totals, and increases.