Like many other people, I love my smart phone, which keeps me connected with the larger world that can go anywhere with me. I also love my laptop，because it holds all of my writing and thoughts. In spite of this love of technology, I know that there are times when I need to move away from these devices and truly communicate with others.

    On occasion, I teach a course called History Matters for a group of higher education managers. My goals for the class include a full discussion of historical themes and ideas. Because I want students to thoroughly study the materials and exchange their ideas with each other in the classroom, I have a rule —no laptop, iPads, phones, etc. When students were told my rule in advance of the class, some of them were not happy.

Most students assume that my reasons for this rule include unpleasant experiences in the past with students misusing technology. There's a bit of truth to that. Some students assume that I am anti-technology. There's no truth in that at all. I love technology and try to keep up with it, so I can relate to my students.

    The real reason why I ask students to leave technology at the door is that I think there are very few places in which we can have deep conversions and truly engage complex ideas. Interruptions by technology often break concentration and allow for too much dependence on outside information for ideas. I want students to dig deep within themselves for inspiration and ideas. I want them to push each other to think differently and make connections between the course materials and the class discussion.

I've been teaching my history class in this way for many years and the evaluations reflect student satisfaction with the environment that I create. Students realize that with deep conversation and challenge, they learn at a level that helps them keep the course materials beyond the classroom.

I'm not saying that I won't ever change my mind about technology use in my history class, but until I hear a really good reason for the change, I'm sticking to my plan. A few hours of technology-free dialogue is just too sweet to give up.

    Petra and Wadi Rum, Jordan

    When it comes to the world's wonderful desert scenery, Jordan's Petra and Wadi Rum has it. Also known as the Valley of the Moon, this place is one of the best due to its amazing desert canyons (峡谷) and rock walls. Participants love exploring its Burdah and Um Fruth, walking to the impressive ancient city.

Kilimanjaro, Tanzania

    The Rongai Route is the best route if the participants of the walking tour want a quiet climb. The Kili Trail permits travelers to witness the region's wilderness, virgin forests, and rare animals. This route, according to many, is the easiest way to reach the top where the breath-taking 360-dcgree sights of natural wonders await.

    Quebec, Canada

    This special environment made up of both the natural and cultural treasures, where fresh water becomes one with the tides (潮汐) of the sea, makes Quebec one of the interesting walking tour destinations in the world. Here is a track that heads to the Saguenay Fjord National Park which is included in the UNESCO World Heritage Site. Adding to the beauty of Quebec are its sparkling waterfalls, inviting lakes, and rare animals.

    Great Smoky Mountain, US

    This region has been named as the ancestral home of the Cherokee Indians, where rich natural wonders combined with interesting history are the major happenings. The rich natural reserve is evident and enjoyed by walking tour participants. What also makes this destination a popular choice is its reputation as the biggest wilderness on the eastern part of the United States.

    It was with heavy hearts that my son and I worked to prepare his car for a milestone journey—the day he moved across the country after twenty years of living under my roof．

    Our work went slowly into the afternoon．The Sunday baseball game came on．Our hometown Cardinals were playing the Atlanta Braves．I overheard bits of the TV broadcast—Atlanta took a two-run lead as we were packing the trunk．After that I became absorbed in glum thoughts about his departure and forgot about the game．Suddenly I heard the door open．“Dad，”he said，“let's watch the game．They're only down by a run．”

    His red-colored eyes instantly told me that he，too，found this to be difficult and wanted to share one last father-son moment．Without hesitation I led the way to the TV set．There，we found the Cards losing 3—1．“Oh，”he said，“they're down two runs．”His voice cracked with doubt．“I thought they were coming back．”“That's fine，”I said，wanting so much to string this moment．“Let's watch anyway．”

    The Cards got to bat last．First a single，and then another．Suddenly the game became very interesting．When David Eckstein parked the third pitch(投球)into the seats，we were transformed，jumping up and down．That's when the magic moment came．The sadness of that day was replaced by the exciting baseball game，something we had done many times together before．

    Then he left．It was a sad day when I helped my son pack and get ready to move away to college．But this moment of joy mixed with sadness made the day，the trip and our life seem so right．

    Edward Hibberd Johnson was an American inventor. He lived in New York City in the 1800s. In 1882, Johnson had an idea. It would change the look of Christmas forever.

    Johnson worked as a boss at a technology company. In 1871, he hired a young man to work for him. The man's name was Thomas Edison. Edison was a great worker. He came up with many new ideas. Later, Edison left to start his own company. Johnson followed him. Johnson started turning Edison's ideas into money. In 1880, Edison invented the light bulb. No one knew how much it was worth. At the time, most homes did not have the electricity to power it. However, Johnson helped start a company to sell the bulbs.

    Before long, Mr. Johnson had a bright idea. Christmas trees were very popular. They were so beautiful because of their candles. Flickering (闪烁的) flames were perfect for Christmas. But they were also dangerous. They could easily start a fire.

    Mr. Johnson thought of a way to fix this. He set up a Christmas tree by one of his windows. Then he took 80 colored light bulbs and hung them around it. The lights were red, white and blue. People on the street stopped to look. They admired the shining Christmas tree. It was so popular that Johnson made it a tradition. Each year he added more lights. In 1884, there were 120 light bulbs on his tree. The lights were not cheap. In 1900, a string of 16 bulbs cost $12. That was a lot of money back then, because people made less. In today's money, that is about $350. But over time, they started to cost less. By the 1930s, colored light bulbs were everywhere.

    Today millions of light sets are sold in America each year. They light 80 million homes. Some of them are now used for other holidays too. They are used on Halloween and Valentine's Day. But it all started with Johnson's Christmas tree.

    In the US, people prefer waiting for a table to sitting with people they don't know. This means a hostess may not seat a small group until a small table is available, even if a large one is. If you are sitting at a table with people you don't know, it is impolite to light up a cigarette first asking if it will disturb them.

    At American restaurants and coffee shops you are usually served tap water before you order. You may find the bread and butter is free, and if you order coffee, you may get a free refill.

    Most cities and towns have no rules about opening and closing time for stores or restaurants, though they usually do make rules for bars. Especially in large cities, stores may be open 24 hours a day.

    Serving in restaurants is often large, too large for many people. If you can't finish your meal but would like to enjoy the food later, ask your waitress or waiter for a "doggie bag". It may have a picture of a dog on it, but everybody knows you're taking the food for yourself.

    Supper and dinner are both words for the evening meal. Some people have "Sunday dinner". This is an especially big noon meal.

    Tips are not usually added to the check. They are not included in the price of the meal, either. A tip of about 15% is expected and you should leave it on the table when you leave. In some restaurants, a check is brought on a plate and you put your money there. Then the waiter or waitress brings you your change.

    Chinese scientists recently have produced two monkeys with the same gene, Zhong Zhong and Hua Hua, using the same technique that gave us Dolly the sheep. These monkeys are not actually the first primates(灵长类)to be cloned. Another one named Tetra was produced in the late 1990s by embryo(胚胎)splitting, the division of an early-stage embryo into two or four separate cells to make clones. By contrast, they were each made by replacing an egg cell nucleus(卵原子核)with DNA from a differentiated body cell. This Dolly method, known as somatic(躯体的) cell nuclear transfer(SCNT), can create more clones and allows researchers greater control over the edits they make to the DNA.

    Success came from adopting several new techniques. These included a new type of microscopy(显微术) to better view the cells during handling or using several materials that encourage cell reprogramming, which hadn't been tried before on primates. Still, the research process proved difficult, and many attempts by the team failed. Just two healthy baby monkeys born from more than 60 tested mothers. This leads to many researchers' pouring water on the idea that the team's results bring scientists closer to cloning humans. They thought this work is not a stepping stone to establishing methods for obtaining live born human clones. Instead, this clearly remains a very foolish thing to attempt, and it would be far too inefficient, far too unsafe, and it is also pointless.

    But the scientists involved emphasize that this is not their goal. There is now no barrier for cloning primate species, thus cloning humans is closer to reality. However, their research purpose is entirely for producing non-human primate models for human diseases; they absolutely have no intention, and society will not permit this work to be extended to humans. Despite limitations, they treat this breakthrough as a novel model system for scientists studying human biology and disease.