The United States is a country of immigrants. It is a place where people from all over the world come to build a better life. Some immigrants bring their families. Some bring a few of their favorite things. Others come alone with nothing but determination. One thing that every immigrant brings with them is their culture.

    American immigration began in 1607 with the colony (殖民地) of Jamestown. In 1620, another group of people left England to build a settlement in America. They wanted to go to a place where they could practice their religion freely. Then many more people left their homes in Europe to build a better life in America. Many also came to America from Africa. By 1770, more than two million people had moved to America. Later on, more people came to the United States than ever before.

    In cities all over America, you can see different cultures that formed this country. Many things that you may think of as being “American” are actually from a foreign culture. Some of the best examples of this are the foods people eat. Pizza and spaghetti are foods that all Americans know and love. But both of them are from Italy. Baseball is an all-American sport. But the hot dogs that people eat during the game are a type of food that was brought to America by German immigrants.

    Over time, pizza and hot dogs have become a part of what is considered to be American food. In the same way, different groups of people have come together to define what an American is. An American can be a person of any background. An American can be of any faith. An American can be of any skin color. They can speak English clearly. They can speak English with an accent. Each new immigrant adds something new to American culture. It will keep changing as more people come to this country.

How Women Were Freed From Their Homes

    As late as 1800, a woman's only place was in her home. Women in business were unheard of. No respectable woman would dream of entering what was strictly a “man's world”. Even if she would, what could she do? Men were sure that no woman could do a job well outside her home.  This was a widely-accepted idea. When the famous Bronte sisters began writing books in 1846, they had to resort to using men's names as aliases.

    Teaching was the first profession opened to women, soon after 1800. But even that was not easy for women to take because most high schools and colleges were open only to men. Oberlin College in Ohio was the first college in America to take in women.

    Nursing was regarded as a respectable profession for women only after Florence Nightingale won high credit for her nursing career and became famous. Miss Nightingale opened the first training school for nursing in 1860 in England.

    The invention of typewriters in 1867 helped to bring women out of their homes to join the business world. Because women are careful and have nimble fingers, businessmen found that they were well suited to this kind of work.

    By 1890, tens of thousands of women were working in schools, hospitals, shops, offices, and factories both in England and the States. Some even managed to become doctors or lawyers. The idea of women working in business and other circles was accepted. 

    As self — driving cars come closer to being common on American roads, much of the rhetoric (说辞) promoting them has to do with safety. About 40,000 people die on U. S. roads every year, and driver errors are linked to more than 90 percent of crashes. But many of the biggest advocates of autonomous vehicles aren't car companies looking to improve the safety of their existing products. Huge backing for self - driving technologies is coming from Silicon Valley giants like Google and Apple.

    Those of us who have studied the relationship between technology and society tend to look more carefully at the motivations behind any technological push. In this case, it's clear that in addition to addressing safety concerns, Silicon Valley firms have a strong incentive (动机) to create a new venue for increasing the use of their digital devices. Every minute people spend on their mobile phones provides data - and often money - to tech companies.

    At present, digital devices and driving are in conflict: There are serious, often fatal, consequences when drivers use smartphones to talk or to text. Regulators and safety advocates look to resolve dial conflict by banning phone use while driving - as has happened in virtually every state. But the tech companies are taking a different approach. The obvious answer for Silicon Valley is creating an antomobile in which continuous cellphone use no longer poses a threat to anyone.

    In recent years, the amount of time adults spend on their mobile devices has grown rapidly. At the moment, it's around four hours a day for the average adult in the U. S. However, that rapid growth is likely to slow down as people run out of time that ' s available for them to use their devices. Unless, of course, there's a new block of time that suddenly opens up. The average American now spends about 48 minutes in a car every day, a sizable opportunity for increased cellphone use.

    So as the public conversation around autonomous cars highlights the safety advantages, don't forget the tech industry ' s powerful desire for more profits, which goes well beyond simply saving us from ourselves.

    North America tours

    Tour North America and discover how the New World became the culturally diverse civilization it is today: the world's greatest melting pot is in your own backyard.

Boston: Colonial History

    Days: 4

    Get your walking shoes ready to follow the footsteps of the American Founding Fathers in Boston. Journey through the landmarks of the American Revolution in this historical city by walking down the Freedom Trail with a Colonial tour guide. Get out of the city with detours to Salem. Lexington, Concord and Plymouth, where you will see where the first shots of the American Revolution were fired.

Civil Rights in the South

    Days: 5

    Journey back to a time of revolution and brotherhood in the heart of the Civil Rights Movement. Follow the path of the marches through Atlanta, Montgomery and Birmingham, as well as the town of Selma, where a peace l protest erupted into what is now called" Bloody Sunday. "Pay respect to the key contributors to civil rights by visiting the Rosa Parks Museum and the home and church of the most famous civil rights activist of them all. Dr Martin Luther King, Jr.

    IL MUNC in Philadelphia

    Days: 4

    The Ivy League Model UN Conference (ILMUNC) is known as a unique educational experience for its focus on international affairs and networking. Students from across the continent will come together to debate and discuss pressing global issues as UN delegates. You can also explore some of downtown Philadelphia's finest attractions including the Philadelphia Museum of Art, the Liberty Bell. Independence Hall before or after the conference.

    Quebec City &Montreal Four Day Spring Tour

    Days: 4

    Montreal and Quebec City are two of the most diverse, beautiful and exciting travel destinations in Canada. Your tour through Quebec's Upper Town includes the beautifully lit National Assembly, Dufferin Terrace, and Chateau Frontenac. Walk along the 17^th-century cobblestone streets of Lower Town, then continue on to Montreal for a visit to Mont Royal, which boasts breathtaking views from the highest point in the cit.

    Book 1: Diary of a Fly—By Doreen Cronin

    40 pages, US $15. 99

    This is the diary of a fly. The fly, when she's not landing on your head or swimming in your soup, is trying to escape her 327 siblings who are driving her crazy. Even though she's little—just like her best friends, Worm and Spider— she wants to be a superhero. This is the story of a little fly who's unafraid to dream big.

    Book 2: Iggy Peck, Architect—By Andrea Beaty

    32 pages, US $15.95

    This book is a story about a kid whose head teacher doesn't recognize his great talent (though he makes buildings out of anything at hand, including table cloths, fruit and chalk) until it saves her life. With Andrea Beatty's rhyming text and David Roberts's interesting illustrations (插图), it will charm creative kids everywhere.

    Book 3: The Chicken-Chasing Queen of Lamar County—By Janice N. Harrington

    40 pages, US $16.00

    Our character here loves to run after chickens, particularly Miss Hen, who's very fat. But, as all farming folks know, this is not a good way to produce happy, productive chickens. What will make her change her ways? The author is a professional storyteller and this book is full of fun, and has great illustrations.

Book 4: Cherry and Olive—By Benjamin Lacombe

    32 pages, US $16.95

    Children's books can quickly take little readers into new worlds, such as the big city, 1930s Georgia, or outer space. This book takes us on a little trip to some European capitals. Cherry is fat and likes books, and she has few friends until she meets a SharPei puppy (沙皮狗). She names it Olive. Through it she finds confidence and friendship. But what will happen when its owner returns?

    Most dog owners have probably been puzzled waiting for their dog to do its business. Instead of just finding a soft area of grass to go number two, they make a whole ritual(仪式) out of it, spinning in a circle before finally squatting(蹲下). Luckily, the ultimate pet owners' question may finally have been answered.

    A few theories have circulated about why dogs might circle before pooping  and most are similar to the reasons they spin before lying down. Trampling around in a circle would flatten the grass around, which would keep tall blades(叶片) from trapping their waste. Another explanation could be that they're scanning for snakes and predators before they become completely occupied.

    But Czech researcher Hynek Burda didn't quite buy into those theories. Dogs evolved from wolves, which didn't need to worry much about tall grass. And if they were scanning their environment, keeping still to listen and sniff would be more effective than giving the area a quick once-over. Instead, Burda suggested that dogs spin to get a feel for the Earth's magnetic pull.

    The Earth has a magnetic field around it protecting it from radiation from space, and some animals seem to use it to get a sense of where its North and South poles are. For instance, it's how birds know which way to migrate. In 2013, Burda published a study in the journal Frontiers in Zoology suggesting dogs have a strong internal compass, too. He and his team spent two years watching 70 dogs poop and pee and recording which way they faced and how strong the magnetic(磁的) field was.

    As it turns out, when the magnetic field was calm, dogs preferred to poop facing either north or south.

    The pattern couldn't explain why dogs like facing the Earth's poles, but the researchers think it might help them remember where they marked their territory.

    If they can remember which way they were facing, they might find it easier to find that spot again. So before you roll your eyes when your dog takes ages to do his business, remember that Fido might just be getting scientific about his potty spot.