Hello! Today on Ask a Teacher we answer a question about punctuation marks from Luay in Syria.
你好！今天，在“请教老师”节目中，我们回答了来自叙利亚 Luay 的有关标点符号的问题。
I hope you can tell me about the difference between punctuation marks such as the semicolon (;), the colon (:) and the comma (,) and between round brackets and square brackets.
希望您能告诉我分号（;）、冒号（:）、逗号（,）等标点符号以及圆括号和方括号的区别。
Luay, Syria.
叙利亚卢艾。
Thank you for writing with this very interesting question. Even native speakers have trouble with these punctuation marks when writing English. Let us begin with the simplest one, the comma.
感谢您写下这个非常有趣的问题。即使是母语人士在写英语时也会遇到这些标点符号的问题。让我们从最简单的逗号开始。
First, you need to understand the sentence: it is a group of words with a subject and a verb that expresses a complete thought.
首先，你需要理解句子：它是一组带有主语和动词的词，表达一个完整的思想。
When part of a sentence expresses a complete thought, and could be a sentence, we call it an “independent clause.” It has a subject and a predicate or verb.
当句子的一部分表达完整的思想并且可以成为句子时，我们将其称为“独立子句”。它有一个主语和一个谓语或动词。
The most common use of a comma is to separate an independent clause and a phrase or a dependent clause. When we read the examples in this lesson, we will say the punctuation marks out loud so listeners can understand where they belong.
逗号最常见的用途是分隔独立子句和短语或从属子句。当我们阅读本课中的示例时，我们会大声说出标点符号，以便听众能够理解它们所属的位置。
Every Thursday, VOA has a new Everyday Grammar lesson.
美国之音每周四都有一堂新的日常语法课。
The independent clause is “VOA has a new Everyday Grammar lesson.” “Every Thursday” is separated by a comma. There are many other uses for commas which you can read about in our Everyday Grammar lesson.
独立子句是“美国之音有新的日常语法课。” “每周四”用逗号分隔。逗号还有许多其他用途，您可以在我们的日常语法课程中了解这些用法。
The colon is two dots, one over the other. It has three main uses. One is to introduce a list of things. The part of the sentence before the colon should be an independent clause. Here is an example:
冒号是两个点，一个在另一个上。它有三个主要用途。一是介绍一系列事情。句子中冒号之前的部分应该是一个独立子句。这是一个例子：
Ashton likes only three kinds of fruit: apples, bananas and cherries.
阿什顿只喜欢三种水果：苹果、香蕉和樱桃。
You should not use a colon when the list is part of the independent clause, as in:
当列表是独立子句的一部分时，不应使用冒号，如下所示：
Ashton likes apples, bananas and cherries.
阿什顿喜欢苹果、香蕉和樱桃。
Note that these things are separated by commas but there is no comma before “and.” That is a debated subject we will not get into today.
请注意，这些内容之间用逗号分隔，但“and”之前没有逗号。这是一个有争议的话题，我们今天不会讨论。
You can also use a colon between two independent clauses when the second one explains the first.
当第二个子句解释第一个子句时，您还可以在两个独立子句之间使用冒号。
We ate all of the ice cream: it was too hot this afternoon .
我们吃完了所有的冰淇淋：今天下午太热了。
Third, you can use a colon to emphasize a phrase or word at the end of a sentence:
第三，您可以使用冒号来强调句子末尾的短语或单词：
After hours of work, we saw what we wanted: a clean house.
经过几个小时的工作，我们看到了我们想要的：一个干净的房子。
Moving on to the semicolon, you may say it looks like a period or a dot above a comma. We use a semicolon to connect two independent clauses that have related subjects. For example,
转到分号，您可能会说它看起来像逗号上方的句点或点。我们使用分号连接两个具有相关主语的独立子句。例如，
I think we should study in the bookstore; my friend works there.
我想我们应该去书店学习；我朋友在那里工作。
You should never use a comma to connect two independent clauses. Note that the semicolon takes the place of any conjunction that might connect two independent clauses. A good test of whether you have used the semicolon correctly is to replace it with a conjunction, that is, “or,” “for,” “and” or “but.” Here is a sentence with a semicolon between the two independent clauses:
切勿使用逗号连接两个独立的子句。请注意，分号取代了可能连接两个独立子句的任何连词。检验是否正确使用分号的一个好方法是将其替换为连词，即“或”、“for”、“and”或“but”。这是两个独立子句之间有分号的句子：
The cat came in the door; it was carrying a mouse.
猫进门了；它带着一只老鼠。
When we use a conjunction, we no longer need the semicolon.
当我们使用连词时，我们不再需要分号。
The cat came in the door, and it was carrying a mouse.
猫进门了，它叼着一只老鼠。
Brackets and parentheses
方括号和圆括号
Your last question was about the marks you call round and square brackets. The round ones are called parentheses. We use them to add some information to help explain what we have written. When reading them aloud, we say “open parentheses” for the one on the left side and “close parentheses” for the opposite one, on the right. For example,
你的最后一个问题是关于你所说的圆括号和方括号的标记。圆形的称为括号。我们使用它们添加一些信息来帮助解释我们所写的内容。当大声朗读它们时，我们对左侧的括号说“左括号”，对相反的右侧的括号说“闭括号”。例如，
I opened a can of food for Makeda (the dog) and put it in a dish.
我为Makeda（狗）打开了一罐食物，并将其放入盘子中。
The square brackets [] have several uses. They are used to put comments or information into direct quotations, to identify errors in text, and to add more information within something that is already in parentheses. Here are examples of the brackets in action:
方括号 [] 有多种用途。它们用于将评论或信息放入直接引用中，识别文本中的错误，以及在括号中已有的内容中添加更多信息。以下是括号的作用示例：
His mother said, “Look, this letter [it was from the university] came for you.”
他的母亲说：“看，这封信（来自大学）是给你的。”
Alex picked up the bag (he thought it held more water [it only had empty bottles]) and shook it.
亚历克斯拿起袋子（他认为里面装的水更多[里面只有空瓶子]）并摇晃。
You may also see brackets around a Latin word, [sic] showing there was a mistaken word in what someone else wrote.
您还可能会看到拉丁词周围有括号，[原文如此]表明其他人写的内容中有一个错误的词。
I hope this answers your question, Luay.
我希望这能回答你的问题，Luay。
What question do you have about American English? Send us an email at learningenglish@voanews.com
您对美式英语有什么疑问？给我们发送电子邮件至learningenglish@voanews.com
Editor's note: An earlier version of this story had an error in reference to one of the sentences. It has been corrected. We thank our listeners and readers for their thoughtful comments which make our stories better.
编者注：这个故事的早期版本在引用其中一个句子时存在错误。已更正。我们感谢听众和读者的深思熟虑的评论，这些评论使我们的故事变得更好。