Coordinating conjunctions connect two elements of equal grammatical status, such as two words, two phrases, or two independent clauses. They show a clear relationship like addition, contrast, choice, cause, or result without making one part dependent on the other. In writing, they help you combine ideas smoothly, avoid repetition, and control the flow of information. The most common coordinating conjunctions are often remembered as FANBOYS.

A coordinating conjunction can join single words, longer phrases, or whole independent clauses. The key idea is balance: both sides should play the same role in the sentence, such as noun with noun, verb with verb, or clause with clause. When the joined elements are not equal, English usually requires a subordinating conjunction instead. Coordinating conjunctions can also join more than two items when used with parallel structure.

Word/Phrase	🇨🇳 中文 单词/短语	Definition	🇨🇳 中文 定义	Example	🇨🇳 中文 示例
word + word	🔤 单词 + 单词	two single words with the same function	🔤 两个具有相同功能的单词	tea and coffee	🔤 茶和咖啡
phrase + phrase	🔤 短语 + 短语	two phrases with the same function	🔤 两个具有相同功能的短语	in the morning or after lunch	🔤 早上或午餐后
clause + clause	🔤 子句 + 子句	two independent clauses	🔤 两个独立子句	I called, but no one answered.	🔤 我打了电话，但没有人接听。

English has seven common coordinating conjunctions: for, and, nor, but, or, yet, so. Each one signals a specific logical relationship between the coordinated parts. Some are frequent in everyday speech like and, but, or, so, while others like for and nor are more formal or less common. Learning the meaning of each conjunction helps you choose the best connector instead of overusing and.

Word/Phrase	🇨🇳 中文 单词/短语	Definition	🇨🇳 中文 定义	Example	🇨🇳 中文 示例
for	🔤 for	reason or explanation, similar to because	🔤 原因或解释，类似于 because	I left early, for I was tired.	🔤 I left early, for I was tired.
and	🔤 and	addition or combination	🔤 增加或并列	She writes and edits.	🔤 She writes and edits.
nor	🔤 nor	negative addition after a negative idea	🔤 否定性附加，紧跟在否定的想法之后	He did not call, nor did he text.	🔤 He did not call, nor did he text.
but	🔤 but	contrast or exception	🔤 对比或例外	I tried, but it failed.	🔤 I tried, but it failed.
or	🔤 or	choice or alternative	🔤 选择或替代	We can walk or take the bus.	🔤 We can walk or take the bus.
yet	🔤 yet	strong contrast, surprising continuation	🔤 强烈对比、出人意料的延续	It is small, yet powerful.	🔤 It is small, yet powerful.
so	🔤 so	result or consequence	🔤 结果或后果	It rained, so we stayed inside.	🔤 It rained, so we stayed inside.

Choosing a coordinating conjunction depends on the relationship you want the reader to understand. And adds information, but and yet introduce contrast, or presents options, and so gives a consequence. For introduces a reason in a more literary style, and nor continues a negative structure. The conjunction you choose shapes emphasis: yet often feels more dramatic than but, and so can feel more direct than therefore.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Use and for addition or sequence	📌 使用 and 进行添加或顺序	She opened the file and started reading.	📌 She opened the file and started reading.
Use but for simple contrast	📌 使用 but 进行简单对比	The plan is risky, but it might work.	📌 The plan is risky, but it might work.
Use yet for unexpected contrast	📌 使用 yet 进行出人意料的对比	He apologized, yet he repeated the mistake.	📌 He apologized, yet he repeated the mistake.
Use or for alternatives	📌 使用 or 进行替代	Call me now or send an email later.	📌 Call me now or send an email later.
Use so for result	📌 使用 so 表示结果	The store was closed, so we went home.	📌 The store was closed, so we went home.
Use for to introduce a reason in formal style	📌 在正式风格中用于引出原因，for	Do not worry, for everything is ready.	📌 Do not worry, for everything is ready.
Use nor to add a second negative idea	📌 使用 nor 连接第二个否定选项	She did not complain, nor did she quit.	📌 She did not complain, nor did she quit.

When a coordinating conjunction connects two independent clauses, English normally uses a comma before the conjunction. This comma helps the reader see that two complete sentences are being linked. If the second part is not an independent clause, the comma is usually unnecessary. For very short clauses, writers sometimes omit the comma, but the standard rule is to include it for clarity.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Use comma + conjunction between two independent clauses	📌 在两个独立子句之间使用逗号+连词	I finished the report, and I sent it to my manager.	📌 I finished the report, and I sent it to my manager.
No comma when joining two words or two short phrases	📌 连接两个单词或两个简短短语时不使用逗号	We bought apples and bananas.	📌 We bought apples and bananas.
No comma when the second part is not an independent clause	📌 当第二部分不是独立子句时不使用逗号	I finished the report and sent it to my manager.	📌 I finished the report and sent it to my manager.
Comma is recommended for clarity even with short independent clauses	📌 即使在短的独立子句也推荐使用逗号以提高清晰度	I came, but I left.	📌 I came, but I left.

Coordinating conjunctions work best when both sides have the same grammatical form, called parallel structure. This makes sentences easier to read and avoids awkward imbalance. Parallelism applies to words, phrases, and clauses, and it becomes especially important when you join longer or more complex items. When parallel structure is consistent, the conjunction clearly signals the relationship rather than forcing the reader to reinterpret the sentence.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Join matching forms like noun with noun or clause with clause	📌 连接匹配的形式，如名词与名词或子句与子句	She likes swimming and running.	📌 She likes swimming and running.
Keep verb forms consistent across the coordination	📌 保持并列中的动词形式一致	He plans to study and to work.	📌 He plans to study and to work.
Use the same clause pattern on both sides when possible	📌 可能的话在两边使用相同的从句模式	She not only called, but she also emailed.	📌 She not only called, but she also emailed.
Use lists with consistent structure when adding items with and or or	📌 添加项时使用结构一致的列表，如使用 and 或 or	The job requires accuracy, patience, and attention to detail.	📌 The job requires accuracy, patience, and attention to detail.

Nor typically follows a negative statement and adds another negative idea of equal weight. It often appears in a more formal structure where the auxiliary verb comes before the subject, especially with full clauses. You can also use nor to connect two negative alternatives, usually paired with neither. Understanding nor helps you avoid double negatives and keeps the sentence logically consistent.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Use nor after a negative clause to add a second negative clause	📌 在否定子句之后使用 nor 来添加第二个否定子句	He was not ready, nor was he willing.	📌 He was not ready, nor was he willing.
Use neither ... nor to connect two negative options	📌 使用 neither ... nor 连接两个否定选项	Neither the manager nor the staff knew.	📌 Neither the manager nor the staff knew.
Use auxiliary inversion with nor in formal clause patterns	📌 在正式的从句模式中使用 nor 的助动反转	She did not agree, nor did she explain.	📌 She did not agree, nor did she explain.
Avoid adding another negative word after nor in standard English	📌 在标准英语中避免在 nor 之后再添加另一个否定词	He did not call, nor did he text.	📌 He did not call, nor did he text.

For and so can both connect clauses, but they differ in tone and typical context. For introduces a reason and sounds more literary or formal than because, and it is mainly used to join clauses rather than single words. So introduces a result and is common in speech and writing, but it can sound informal when overused. In more formal writing, therefore or consequently may replace so, but so remains correct as a coordinating conjunction.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Use for to give a reason with a formal tone	📌 使用 for 以正式语气给出原因	We stayed inside, for the weather was dangerous.	📌 天气危险，因此我们待在室内。
For usually links two independent clauses, not single words	📌 For 通常连接两个独立子句，而不是单个词	I rested, for I was exhausted.	📌 我休息，因为我已疲惫。
Use so to show a result from the first clause	📌 使用 so 表示前一子句的结果	The deadline moved, so we adjusted the schedule.	📌 截止日期移动，因此我们调整了日程。
In very formal writing, consider alternatives to so for a more academic tone	📌 在非常正式的写作中，考虑用 therefore 的替代以获得更学术的语气	The deadline moved; therefore, we adjusted the schedule.	📌 The deadline moved; therefore, we adjusted the schedule.

But and yet both signal contrast, but yet often suggests a stronger or more surprising contrast. But is the most neutral and common option for opposition or exception. Yet can highlight that the second clause is unexpected given the first clause, which can create a more emphatic effect. Choosing between them lets you control nuance without changing the basic grammar of coordination.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Use but for neutral contrast	📌 使用 but 来实现中性对比	The room is warm, but the floor is cold.	📌 房间很暖和，但地板很冷。
Use yet for stronger or more surprising contrast	📌 使用 yet 实现更强烈或更出乎意料的对比	The method is simple, yet it works reliably.	📌 方法简单，但它可靠地工作。
Yet commonly appears after a comma when linking independent clauses	📌 Yet 通常在连接独立子句时出现在逗号之后	He was warned, yet he ignored the signs.	📌 He was warned, yet he ignored the signs.

Coordinating conjunctions are one way to connect ideas, but punctuation choices affect style and clarity. A semicolon can connect two related independent clauses without a conjunction, while a semicolon plus a coordinating conjunction is usually unnecessary. A comma alone cannot correctly join two independent clauses in standard writing, so the conjunction or a stronger punctuation mark is needed. Knowing these options helps you avoid run-ons and choose the tone you want.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Do not join two independent clauses with only a comma in standard writing	📌 在标准写作中切勿仅用逗号连接两个独立子句	I called, but no one answered.	📌 I called, but no one answered.
Use a semicolon to link closely related independent clauses without a conjunction	📌 使用分号在不使用连词的情况下连接密切相关的独立子句	I called; no one answered.	📌 I called; no one answered.
Use period to separate ideas for a stronger break	📌 使用句号分隔想法以获得更强的断裂	I called. No one answered.	📌 I called. No one answered.
Avoid semicolon + coordinating conjunction in most cases	📌 在大多数情况下避免分号+并列连词	I called, and no one answered.	📌 I called, and no one answered.