If you've ever owned a chimney, you know that it can get pretty dirty. There's a whole lot of soot(烟灰) that gets stuck on the inside. That stuff has to get cleaned, or you could have a serious fire risk. While nowadays we have easier ways of doing this dirty job, in the way back days somebody used to climb up the chimney and clean all that soot. And the thing is, not just anybody could do it.

    You had to be really small to fit up in the chimney, so they used to give the task to kids – some as young as four or five years old. They worked for their boss known as a master-sweep. They were often covered in soot, and were very likely to get burned. They often developed what became known as soot wart, a form of cancer.

    Are your unfairness bells ringing? William Blake's certainly were. The physical dangers and widespread unfairness of the chimney-sweeping job really stuck in his throat, so much so that he wrote not one, but two poems called “The Chimney Sweeper”.

    The first poem (the one we're discussing here)was published in 1789 in a book called Songs of Innocence. These little poems took children and the joys of childhood innocence as their subject. As you've probably guessed by now, many of the poems in Songs of Innocence, like “The Chimney Sweeper”, are about the ways in which childhood innocence is destroyed by unkind old adults. For Blake, innocence is, in many ways, a total joke. It doesn't exist, because it's always taken away by the realistic world – chimney-sweeping, death, poverty, etc.

    What does a five-year-old chimney sweeper in 18th-century England have to do with you? More than you might think. It is reported that 150 million kids are in child labor in developing countries. Many of them work long hours and face dangerous health risks. Like Blake's chimney sweeper, these kids are not even given a chance at innocence because experience keeps getting in the way.

    Last year I ruined my summer vacation by bringing along a modern convenience that was too convenient for my own good: the iPad. Instead of looking at nature, I checked my email. Instead of paddling a small boat, I followed my Twitter feed (推特简讯). Instead of reading great novels, I stuck to reading four newspapers each morning. I was behaving as if I were still in the office. My body was on vacation but my head wasn't.

    So this year I made up my mind to try something different: withdrawal (退出) from the Internet. I knew it wouldn't be easy, since I'm bad at self-control. But I was determined. I started by giving the iPad to my wife.

    The cellphone signal at our house was worse than in the past, making my attempts at cheating an experience in frustration (沮丧). I was trapped, forced to go through with my plan. Largely cut off from e-mail, Twitter and my favorite newspaper websites, I had few ways to connect to the world except for radio and how much radio can one listen to, really? I had to do what I had planned to all along: read books.

    This experience has had a happy ending. With determination and the strong support of my wife, I won in my vacation struggle against the Internet, realizing finally that it was I, not the iPad, that was the problem.I knew I had won when we passed a Starbucks and my wife asked if I wanted to stop to use the Wi-Fi. “ I don't need it,” I said.  

    However, as we return to post -vacation life, a harder test begins: Can I continue when I'm back at work? There are times when the need to know what's being said right now is great. And I have no intention of giving up my convenience completely. But I hope to resist the temptation (诱惑) to check my e-mail every five minutes, which leads to checking my Twitter feed and a website or two.

    I think a vacation is supposed to help you reset your brain to become more productive. Here I hope this one worked.

    People are being lured(引诱) onto Facebook with the promise of a fun, free service without realizing they're paying for it by giving up large amounts of personal information. Facebook then attempts to make money by selling their data to advertisers that want to send targeted messages.

    Most Facebook users don't realize this is happening. Even if they know what the company is up to, they still have no idea what they're paying for Facebook because people don't really know what their personal data is worth.

    The biggest problem, however, is that the company keeps changing the rules. Early on, you keep everything private. That was the great thing about Facebook—you could create your own little private network. Last year, the company changed its privacy rules so that many things—your city, your photo, your friends' names—were set, by default(默认) to be shared with everyone on the Internet.

    According to Facebook's vice-president Elliot Schrage, the company is simply making changes to improve its service, and if people don't share information, they have a “less satisfying experience”.

    Some critics think this is more about Facebook looking to make more money. Its original business model, which involved selling ads and putting them at the side of the page, totally failed. Who wants to look at ads when they're online connecting with their friends?

    The privacy issue has already landed Facebook in hot water in Washington. In April, Senator(议员) Charles Schumer called on Facebook to change its privacy policy. He also urged the Federal Trade Commission to set principles for social-networking sites. “I think the senator rightly communicated that we had not been clear about what the new products were and how people could choose to use them or not to use them，” Schrage admits.

    I suspect that whatever Facebook has done so far to invade our privacy is only the beginning, which is why I'm considering deactivating (撤销) my account. Facebook is a handy site, but I'm upset by the idea that my information is in the hands of people I don't know. That's too high a price to pay.

    Four years ago your friends congratulated you and your father talked big continuously. Four years ago you walked among the gothic towers and weathered traditions that sew our community together. But what's next, will I make friends, or I will measure up? And maybe you quietly wondered why a place like Yale, a place that sparked the drive of presidents, a place that raised the world-famous scholars, a place that trained Pulitzer Prize winners, would ever want you? I hope you had these questions because otherwise I might have embarrassed myself. I admit I asked all of these and more.

    I took an unconventional path to Yale. Five years ago I was working the evening shift at a clothing store in the suburbs of Virginia. My family had moved every year for the past five years and our finances were so consumed that retirement was not a possibility. Worse yet, my son was a junior at an Ivy League college in New Jersey and hearing about his privileged friends often reminded me of all the things I wanted to give him but couldn't.

    When I told him this he relied, “If you really want to spoil me, spoil yourself. ”Then he took my hands and told me I had a brilliant mind and deserved better than everything I had ever known.

    That summer I started community college while working full-time. Education was my second chance. I awoke my curiosity, vitality( 活力) and dignity that I never knew I could feel. When I read Eliot, Miller and Morrison, it was as if I were the first person to have ever read them, as if they were secret insights into the human soul and situations and I knew I couldn't stop.

    Walking among these gothic towers, among these traditions, and among this brilliant, vibrant and unapologetically eclectic Class of 2014 has been inspiring. Whether debating issues in class, or chatting over coffee, I have enjoyed, learned and loved every moment I have shared with you. You have made me a better person and I only hoped I have helped in some way to do the same for you.

    And yet even now this is dreamlike. Four years ago I was convinced no one would want me, I wouldn't measure up and as far as knowing what was next, I supposed I had resigned myself to more of the same. But I've come to learn that nothing great can really be accomplished without a healthy dose of terror. No one ever wrote epic(史诗般的) poems, built monuments or told bedtime stories about people who played it safe.

    I was terrified when I came to Yale. A big part of me thought I wasn't good enough. But a big part of life is ignoring the naysayers(反对者) especially the one inside you. Most people are stopped from doing great things by no one but themselves. I learned to tell myself to shut up. Sometimes in the mirror in the morning and others times in the dark before I went to bed. I came to realize once I could overcome my own fear I could overcome just about anything. If you haven't felt this yet I recommended it: it's the greatest joy you'll ever know.

    You've likely all met your own fear and misgivings(担忧、害怕). I charge you to tell that voice to shut up when necessary because in the end your greatness will not be about IQ but about the sincerity of your ambitions, the toughness of your character and your unwillingness to compromise in the face of difficulty, fear and uncertainty.

    And should someone tell you that it can't be done, or you're not good enough or it's not worth the trouble? Should others ask you to take the safe route, or stick to the path of least resistance? Should people say it's too late or your dreams are impractical? Look them in the eye, laugh a little and let them know “Nothing is impossible”.

Dear Max,

It must seem a little odd to get a letter from your own mother who m you see every day, but I hope you will read this and take what I have to say seriously. 

I bought you a phone for your 12th birthday because you wanted one so much, and all your friends have one. I know you love your phone, but I wonder whether you are aware of just how much you use it. 

From my perspective, it seems that you are constantly checking your phone for notifications（通知） or messages. You even do this when we're having a family meal in a restaurant or when I'm talking to you. You may not realise this, but whenever you feel even slightly bored, you check your phone. You never seem to relax. You're constantly on alert, and I don't think this is very good for you. We all need to switch it off every now and then. And if I ask you to leave your phone at home when we go out, you sulk（生气） and get twitchy, almost as if you're suffering withdrawal symptoms（戒断症状）. It's like your phone is a drug.

I have tried to talk to you about this, but whenever I ask you to put down your phone and look at me, you say "in a minute". Unfortunately, "in a minute" never comes, and we never talk. I can't actually remember the last time we had a proper face-to-face conversation. I even have to message you to let you know dinner is on the table! That's why I decided to put my concerns in a letter to you.

Please don't think I am writing this letter to punish you or to nag（唠叨） you. I know you are a good boy. I don't think you want to hurt me or be rude intentionally. However, I recently heard about something called "nomophobia"—the fear of being without a phone. It's a real illness and I'm worried whether you have it. I really think it would be a good idea if we all went to see an addiction expert together so we can all have a discussion about this serious problem. I know you won't want to, but I'm very concerned about you. Please take some time to think about what I have written. Then let's talk.

Mum, 

For centuries Antarctica has attracted people from around the world. Explorers sought to travel there. Scientists have studied weather, wildlife, and geology there for decades. {#blank#}1{#/blank#} In the last few decades, though, scientists have reported that the ice is melting.

 {#blank#}2{#/blank#} That's a difficult question to answer. The loss of ice in Antarctica has not been linear (直线的). That means it isn't a steady decrease. In fact, the rate of melting can vary greatly from year to year. Still, scientists warn that the continent's ice sheet is shrinking.

{#blank#}3{#/blank#} Climate change is warming the world's oceans and affecting the currents (洋流) of the Earth's oceans. These currents are bringing more warm water to Antarctica than ever recorded.

Today, the planet is warming at a rate that alarms scientists. {#blank#}4{#/blank#} The effects of such a rise could cause major problems. It will increase flooding, especially in areas near shores. A large rise in sea level could even make some regions uninhabitable. This could cause millions around the world to become climate refugees (难民).

Can humans stop Antarctica from melting? Probably not — but experts do believe people can slow the process. How can you help? Pay attention to your carbon footprint. {#blank#}5{#/blank#} Only changes on a large, global scale (范围) can truly make a difference to Antarctica.

A. How quickly is Antarctica melting?

B. Is human activity contributing to the melting of Antarctica's ice?

C. The ice of Antarctica is the result of thousands of years of snow.

D. West Antarctica is the region most affected by these warm waters.

E. Talk with your family about ways to reduce your use of fossil fuels.

F. If this continues, melting ice could lead to a serious rise in sea level.

G. Experts say the melting of Antarctica's ice sheet is caused by rising temperatures.