你写的每一篇文章或作业都必须以引言开始. 我们可以把它想象成一个倒金字塔. In such a pyramid, you begin by presenting a broad introduction to the topic and end by making a more focused point about that topic in your thesis statement. 引言有三个基本部分，每个部分都有一个特定的目的.
The first part is the "attention-grabber.“你需要让读者对你的话题感兴趣，这样他们才会想继续读下去. 你还想以一种新颖的、原创的方式来做这件事. 例如, 虽然你可能很想用字典的定义来开始你的文章, 这种技术已经过时了，因为它已经被广泛滥用. 相反，你可以尝试以下方法之一:
Use rhetorical questions that place your readers in a different situation in order to get them thinking about your topic in a new way.
If you have a personal connection to the topic, 你可以用一件轶事或故事来吸引读者的情感.
例如, if you were writing a paper about drunk drivers, you might begin with a compelling story about someone whose life was forever altered by a drunk driver: "At eighteen, Michelle had a lifetime of promise in front of her. 她拿着田径奖学金上大学，成绩很好，交了很多朋友. Then one night her life was forever altered…"
From this attention grabbing opener, 你需要进入介绍的下一部分, 在这个过程中，你要提供一些关于文章特定目的的相关背景. This section helps the reader see why you are focusing on this topic and makes the transition to the main point of your paper. 因此，这部分有时被称为引言的“过渡”部分.
In the example above, 关于米歇尔的轶事可能会引起读者的注意, but the essay is not really about Michelle. The attention grabber might get the reader thinking about how drunk driving can destroy people's lives, but it doesn't introduce the topic of the need for stricter drunk driving penalties (or whatever the real focus of the paper might be).
因此, you need to bridge the gap between your attention-grabber and your thesis with some transitional discussion. In this part of your introduction, you narrow your focus of the topic and explain why the attention-grabber is relevant to the specific area you will be discussing. You should introduce your specific topic and provide any necessary background information that the reader would need in order to understand the problem that you are presenting in the paper. 您还可以定义任何读者可能不知道的关键术语.
Continuing with the example above, we might move from the narrative about Michelle to a short discussion of the scope of the problem of drunk drivers. 例如，我们可以说:“米歇尔的故事不是孤立的. 每年有XX(数目)人死于酒后驾车事故." You could follow this with a short discussion of how serious the problem is and why the reader should care about this problem. 这有效地将读者从米歇尔的故事转移到你的真实主题, 有必要对酒后驾车进行更严厉的处罚吗.
最后, the introduction must conclude with a clear statement of the overall point you want to make in the paper. This is called your "thesis statement." It is the narrowest part of your inverted pyramid, 它准确地陈述了你的文章要讨论的内容.
在这种情况下，你的论文将是你试图提出的点，酒后驾驶. 你可能会主张更好地执行现有法律, enactment of stricter penalties, or funding for education about drinking and driving. 无论是哪种情况，你的论文都应该清楚地阐述你的论文想要表达的主要观点. Here's an example: "Drunk driving laws need to include stricter penalties for those convicted of drinking under the influence of alcohol." Your essay would then go on to support this thesis with the reasons why stricter penalties are needed.
In addition to your thesis, 你的引言通常可以包括一个“路线图”，解释你将如何捍卫你的论文. This gives the reader a general sense of how you will organize the different points that follow throughout the essay. 有时候，“地图”被整合到主题语句中, and sometimes it is a separate sentence. Below is an example of a thesis with a "map."
“因为酒驾会导致不必要的过早死亡, permanent injury for survivors, and billions of dollars spent on medical expenses, 酒后驾车的司机应面临更严厉的酒后驾驶处罚." The underlined words here are the "map" that show your reader the main points of support you will present in the essay. They also serve to set up the paper's arrangement because they tell the order in which you will present these topics.
A final note: In constructing an introduction, make sure the introduction clearly reflects the goal or purpose of the assignment and that the thesis presents not only the topic to be discussed but also states a clear position about that topic that you will support and develop throughout the paper. In shorter papers, 引言通常只有一到两段, but it can be several paragraphs in a longer paper.
虽然对于短文来说，引言通常只有一段, 较长的论证或研究论文可能需要更实质性的介绍. The first paragraph might consist of just the attention grabber and some narrative about the problem. Then you might have one or more paragraphs that provide background on the main topics of the paper and present the overall argument, concluding with your thesis statement.
Below is a sample of an introduction that is less effective because it doesn't apply the principles discussed above.
Everyone uses math during their entire lives. 有些人成年后在工作中使用数学，有些人小时候使用数学. The topic I have chosen to write about for this paper is how I use math in my life both as a child and as an adult. 作为一个成年人，我用数学来平衡我的支票簿和预算我每个月的开支. 当我还是个孩子的时候，我用数学来经营一个柠檬水摊. I will be talking more about these things in my paper.
在上面的介绍中，开场白并不能抓住读者的注意力. 相反，它是对一个显而易见的平凡事实的陈述. The second sentence is also not very specific. 一个更有效的注意力吸引者可能会指出一个具体的, and perhaps surprising, instance when adults use math in their daily lives, 为了向读者展示为什么这是一个需要考虑的重要话题.
Next the writer "announces" her topic by stating, “我选择的写作主题是关于……”虽然有必要介绍你的特定主题, 你要避免发布泛泛的公告来引用你的作业. This technique is not as sophisticated and may distract the reader from your larger purpose for writing the essay. 相反，你可以试着让读者明白为什么这是一个值得讨论的重要话题.
最后，这个示例的介绍缺乏一个明确的主题声明. The writer concludes with a vague statement: "I will be talking more about these things in my paper.这种陈述可以被称为“目的陈述”,其中作者陈述了将要讨论的话题. 然而, it is not yet working as a thesis statement because it fails to make an argument or claim about those topics. A thesis statement for this essay would clearly tell the reader what "things" you will be discussing and what point you will make about them.
Now let's look at how the above principles can be incorporated more effectively into an introduction.
"A penny saved is a penny earned," the well-known quote by Ben Franklin, is an expression I have never quite unders太d, because to me it seems that any penny—whether saved or spent—is still earned no matter what is done with it. My earliest memories of earning and spending money are when I was ten years old when I would sell Dixie cups of 太-sweet lemonade and bags of salty popcorn to the neighborhood kids. 从很小的时候起，我就学会了理财的重要性以及其中涉及的数学技能. I learned that there were four quarters in a dollar, and if I bought a non-food item—like a handful of balloons—that I was going to need to come up with six cents for every dollar I spent. I also knew that Kool-Aid packets were 25 cents each or that I could save money and get five of them for a dollar. 今天, 然而, 理财需要知道的不仅仅是10美分的哪种组合, 五分, and one-penny candies I can get for a dollar. 今天，正确的资金管理包括了解利率, balancing checkbooks, 纳税, estimating my paycheck, and budgeting to make ends meet from month-to-month.
作者用赚到钱和花钱的具体例子来跟踪这个“吸引注意力的东西”. Compare how the specific details of the second example paint a better picture for the reader about what the writer learned about money as a child, rather than this general statement: "As a child, I used math to run a lemonade stand." In the first introduction, 这句话让读者猜测作者是如何使用数学的, 但在第二段介绍中，我们可以看到这个孩子做了什么，学到了什么.
请注意, 太, how the reader makes the transition from the lessons of childhood to the real focus of her paper in this sentence: "今天, 然而, money management involves knowing…."
这个过渡句有效地连接了开头的叙述和文章的主要观点, 她的论点是:“如今，正确的资金管理需要了解 利率, balancing checkbooks, 纳税, estimating my paycheck, and budgeting to make ends meet from month-to-month." This thesis also maps out for the reader the main points (underlined here) that will be discussed in the essay.