China is the biggest market in the world, and many countries such as Germany, the USA, the UK and Russia do a lot of business in China. Let's have a look at some important tips to help you be successful when dealing with these nationalities.

    First, you must be punctual (准时的) with Germans. Even 5 minutes late makes a bad impression. Being punctual is also very important in the USA. In the UK, it's important to be punctual for business meetings, but nobody expects you to be on time for a social event. Half past seven really means a quarter to eight, or even eight o'clock! With Russians, you should always be on time, though it is not unusual for them to be one or even two hours late!

    It is best to dress formally and wear dark colours when you meet people from all the four countries. In Russia, designer clothes are very common. Don't be surpri if you go to an office in the UK on a Friday and find everyone wearing jeans. Many companies have “dress down Friday”, when people wear casual (随便的) clothes.

    In Germany, first names are only used by family members and close friends, so be prepared to use titles and last names. In the USA you will usually be invited to use first names almost immediately. The British are quite informal and using first names in business is more and more common, especially among younger people. In Russia, however, nobody uses first names, so use titles and last names.

    In conversation, the British and the Americans value humour, and both like to talk about sport. The weather is also a good topic of conversation with the British and the Americans, but avoid talking about politics. In Russia, say positive（肯定的） things about their country, but avoid making complaints. The Germans, however, prefer to get straight down to business!

    So, use these tips, and you will be on your way to a successful international business career!

    South Africa is a multiethnic society encompassing a wide variety of cultures, languages, and religions. It has 11 official languages. If you want to say hello, it's "sawubona" in Zulu, and "hallo" in Afrikaans. Now, South Africa's school children may start using "ni hao" to say hello.

    The country's education minister says, the nation is adding the Mandarin language teaching in some schools. Mandarin is the official spoken language of China. That country is a major trading power for South Africa.

    A recent agreement between the two nations centers on five areas of cooperation. They include development in basic education, school books and lessons, mathematics and science, teacher training and career education and research.

    South Africa officials have not said how much they teaching Mandarin will cost. Troy Martens is an officials with South Africa's Ministry of Basic Education. She says the new partnership is extremely valuable.

    A public opinion study last year found that South Africans have mixed feelings about China. The survey showed 46 percent of South Africans do not like the spread of Chinese ideas and customs in their country, the results also showed that 60 percent dislike Chinese music, movies and television.

    But Ms Martens said Chinese trade is more important than those feelings. She said it is extremely helpful to learners in South Africa to study Mandarin as well as Chinese culture. And she said not every school will offer Mandarin.

    “Now this will not be compulsory, it will not be for every school, and it will not be for every child. But for schools that feel they have the capacity to offer Mandarin as a subject, we think it is a great opportunity for South African learners to be exposed to this international type of language,” said Martens.

    Lisette Noonan heads the 80-year-old Pretoria Chinese School in South Africa's capital. The school serves about 500 students from kindergarten to grade 12. Every student studies Mandarin.

    Ms Noonan says the school welcomes the new cooperation between South Africa and China. She said it is in the best interests of children to study Mandarin. She said that especially true with China becoming what she called “a huge economic power in the world”

    When it comes to the Internet, people talk about the password most. Actually, it's been under fire for a long time. Research has shown that passwords are not a very good way to protect sensitive information.

    People would use some random characters, numbers and symbols. Furthermore, a unique password would be used for every site or application the user uses. Unfortunately, the longer and more complex passwords become, the more people are likely to forger them. Therefore, they use the same password for every service or application. These are all big no-noes and essentially defeat the purpose of a password.

    Google is trying to kill off passwords on Android devices by introducing the Trust API, which does what simple passwords cannot and gives developers a framework for securing their application using a number of security systems and metrics(衡量标准)on the device. A Trust Score will be generated based on a number of metrics including your device location, face scanning, fingerprints, and the things like your typing speed or the way you speak. Taken one at a time, these metrics are not secure. But taken together, these metrics will help recognize the real “you”.

    The good news is that Google has already been testing this on real world data. Google has proven the Trust API works. Next Google will run tests will some banks to see if the Trust API meets their needs before rolling out the system on Android phones later. It may take another year for apps and popular sites to start using the Trust API.

    This is a pretty exciting change. Passwords have been around for a lone time. Although the security of systems has been improved, the usability of systems hasn't been proved much. Google appears to have the best of them. Maybe that never-ending conflict between security and convenience will be able to take a break once the Trust system comes out.

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    The holidays are a time to give. These organizations are looking for volunteers and donations (捐赠). Read on to learn more about them. Then, find out how you can help.

    American Red Cross

    This holiday season, your donation can make a difference at home and abroad. The American Red Cross is making it easy to help people who have experienced natural disasters (灾害), members of the U.S. armed forces, and children all over the world. With just one click (点击), you can give the gift of caring.

    National Military Family Association

    Each year hundreds of Americans serve both at home and abroad to keep our country safe. This holiday season, we can help serve them. Through donations, National Military Family Association helps to provide military members and their families with scholarships, family retreats, camp programs for kids, and more.

    Network for Good

    This website allows its users to donate to organizations and discover volunteer chances. After natural disasters, the Network for Good provides a system of help and support for those in need. The website also offers tips to kids who want to give. Visit the website to find out how you can help make someone's holiday season shine bright.

    Make-A-Wish Foundation

    Sometimes all it takes is one wish made come true to make someone smile. The work of Make-A-Wish Foundation is to make the wishes come true. Through support and donations, the foundation has made dreams come true for hundreds of thousands of children with serious illnesses.

    If you want to help others, don't wait for a better time. Help now! Your help will be valued highly.

     Books at Amazon :Best sellers of the month—Feb, 2018

    Freshwater by Akwaeke Emezi—February 6, 2018

    Hardcover :$15.91Audio CD :$29.99

    An extraordinary novel. Freshwater explores the amazing experience of having another self. It centers around a young Nigerian woman, Ada, who develops separate selves within her as a result of being born “with one foot on the other side.” Freshwater is a sharp call of a rare way of experiencing the world, one that shows how we all construct our identities.

    Milk and Honey by Rupi Kaur—February 16 , 2018

    Hardcover: $ 18. 00 Paperback: $ 8.99 Audio CD :$8.99

    A collection of poetry and prose (散文)about survival. About the experience of violence, abuse(虐待), love , loss, and femininity (女性). It is split into four chapters ，and each chapter serves a different purpose. Deals with a different pain. Heals a different heartache. Milk and Honey takes readers through a journey of the most bitter moments in life and finds sweetness in them because there is sweetness everywhere;if you are just willing to look.
     Educated by Tara Westover—February 13, 2018

    Hardcover: $ 16.80 Paperback: $ 28.00 Audio book: $6.00 Audio CD :$8.99

    An unforgettable biography about a young girl who, kept out of school, leaves her survivalist family and goes on to earn a PhD from Cambridge University. Educated is an account of the struggle for self-invention. It is a tale of fierce family loyalty, and of the sadness that comes from severing one's closest ties.

    Force of Nature by Jane Harper—February 20, 2018

    Hardcover: $17.10 Paperback: $ 23.41 Audio book:Free Audio CD :$ 34. 15

    An attractive novel from the author of the Sunday Times top 10 best seller. Five women go on a hike. Only four return. When five colleagues are forced to go on a corporate retreat in the wilderness , they reluctantly pick up their backpacks and start walking down the muddy path. But one of the women doesn't come out of the woods. And each of her companions tells a slightly different story about what happened.

    A new study suggests climate conditions in the Sahara Desert, one of hottest, driest and most deserted areas in the world, have changed from wet to dry a about every 20,000 years.

    But previous evidence has suggested the Sahara did not always experience such extreme heat and dry conditions. At times, the Sahara Ranged to a very wet climate. This permitted plants and animals to develop and grow and led to the creation of human settlements. Now, they have discovered more evidence, which, the lead researcher David Mc Gee says, supports the idea that the Sahara's climate kept changing between wet and dry about every 20,000, years.

    McGee reported these climate changes were mainly driven by changes in the Earth's(地轴)as the planet travels round the sun .This process affects the amount of sunlight between seasons. Every 20,000 years the Earth receives more strong summer sunlight. When the Earth's axis changes again, the amount of sunlight is reduced. This season change happened continuously every 20,000 years. The other part of the season produced rainy conditions, resulting in a wetter, greener, plant-rich environment. When the rainy activity weakens, the climate becomes hot and dry, like the Sahara remains today.

    The scientists based their research on dust collected from ocean sediment(沉积物)in the Atlantic Ocean bottom off the coast of West Africa. The dust contained layers (层)of ancient sediment built up over millions of years. Each layer could contain traces of Saharan dust as well as the remains of life forms. This information was used to assess over what time period the dust had built up. This led to the overall finding that the Saharan changes from wet to dry climates happened every 20,000 years.

David McGee said that today we only see the Sahara Desert as an extremely deserted and "inhospitable" place. The new study suggests that the area's climate has changes between grasslands and a much wetter environment, and back to dry climates, even over the last quarter million years. McGee says he thinks the latest research can be valuable in studying the Sahara's history as it relates to human settlement.