Until now, the oldest evidence of human ancestors outside of Africa was in Dmanisi, Georgia. Here fossils of short people thought to be early Homo erectus date back to about 1.85 million years—just after the species appears in Africa. The oldest evidence of early human activity in China can date back to 1.5 million to 1.7 million years ago, which has suggested that they didn't leave Africa until 2 million years ago or so—and made it to eastern Asia even later.
Now evidence from the site of Shangchen in the Loess Plateau approximately 1,200 kilometers southwest of Beijing is shaking up that view. More than 2 million years ago, our ancestors were already world travelers, which shows that the ancestors of modern humans left Africa at least 250,000 years earlier than thought. It also supports a minority view that a key human ancestors, Homo erectus, may have originated in Asia, not in Africa.
The same team, led by geologist Zhao Yuzhu of the Guangzhou Institute of Geochemistry at the Chinese Academy of Science found that the stone tools range in age from 1.6 million to 2.1 millions years ago. This indicates humans—the family that includes humans and our ancestors—got out of Africa at least a quarter of a million years earlier than thought, and occupied Shangchen on and off for more than 850,000 years, the team reports today in Nature.
"The dates are convincing," Zhao Yuezhu says, which suggest humans were already remarkably adaptable to the changeable climate by 2.1 millions ago—even though they had not yet developed the even bigger brains, long legs, or more advanced tools seen in later humans. Although the identity of these early travelers all over the world is unknown, the new dates raise the possibility that H. Erects weren't the first humans to leave Africa.
1）简介爱鸟社；
2）活动时间和地点；
3）活动内容。
注意：1）词数100左右；
2）可以适当增加细节，以使行文连贯。
1）你的发现；
2）你的倡议。
注意：
1）词数80左右；
2）可以适当增加细节，以使行文连贯。
Dear fellow students,
Many people think only professionals—engineers, accountants, teachers, etc. —have careers. Even if you've never had a paid job, you still have a career. Your career is the sum of your life and work. It includes all your activities and experiences. Your schooling, your volunteer work, and even your relationships with your family are all big parts of your career.
During your career, you will have a variety of jobs, occupations and roles. People used to think of a job as full-time, permanent, paid work done for an employer at a work site. But in our changing world, a job is a set of duties or tasks. It can be paid or unpaid. Even someone who is self-employed has a job.
An occupation is a group of jobs with similar responsibilities that require a common set of skills. Programmers may have permanent or temporary jobs working for specific employers, be self-employed, work full-time or part-time, be paid for their work or volunteer their services. They may change jobs or hold several jobs at one time, but until they change the type of duties or tasks they perform, they are still computer programmers.
We all play a number of roles in our lives and our roles often change over time. For example, Kris works four days a week as a receptionist in a clinic and takes evening courses in social work. She also sews gymnastic wear for her neighbor who sells it at summer markets. Now Kris has at least three roles.
A. A role is a part you play.
B. Actually everyone has a career.
C. In other words, your career is your life story.
D. For example, computer programmer is an occupation.
E. As a matter of fact, a job is different from a role in some way.
F. It can be completed at a work site, at home, or somewhere else.
G. The following is about your work, your family, and your life story.
I was born with a heart disease. As I grew up, parts of my heart started to 1 and I was often out of breath. So when I was eight, the doctors opened my chest to 2 it. When they saw the state of my heart, they told my parents, "We don't expect him to 3 the night." I was in and out of a coma (昏迷) for three months. Every day the fact that I wasn't 4 was a good thing.
Finally, the doctors 5 I'd be better off at home—saying that I wasn't going to live long. But I 6 and had something close to a 7 childhood. As a teenager, I began to 8heart failure again. But I was 9 to go to college, become a manager and get married to Jo.
I started my own10 so I could work flexible(灵活的)hours, 11Jo and I had two children: Josh and Liam. I 12 to keep a good standard of life for everyone, even when I was waking up feeling sick every morning. By January last year, my heart failure was so 13 I often couldn't walk more than a few yards.
I was worried about not being around for my 14 . I had to explain to Josh that the 15 telling me an organ(器官)had been found could come any time and I'd be rushed to hospital, perhaps 16 I could say goodbye. A few days later, the phone rang and Josh said, "Is that the doctor with your new 17?"However it was 18 a salesman.
May 4 was the day a transplant (移植)match was found. I was out of hospital within five weeks and, within a few 19 , feeling much better. By October, I was taking part in a 30-mile bike ride.
These days I spend a lot of time talking to kids with heart 20 . I want to support others who've had a hard time.
Are you a high school student? Then consider spending your summer at Harvard, where you can explore a variety of collegelevel courses, and live and learn with students from different countries.
TWO CHOICES TO CHOOSE FROM：
PreCollege Program
A twoweek residential (住宿的) experience featuring noncredit courses
SESSION (期) Ⅰ：June 24—July 6
SESSION Ⅱ：July 8—20
SESSION Ⅲ：July 22—August 3
The program features：
●A choice of over 100 noncredit courses designed for precollege students.
●Oncampus (校内的) housing with fellow precollege students and residential staff.
●Structured days, with weekday class meetings and precollege activities.
The fee for the Harvard PreCollege Program session is $4,500.
The PreCollege Program cost includes：
●Courses
●Housing and all meals
●Offcampus activities—transportation and most entrance fees
Secondary School Program
College courses for credits in a sevenweek session, June 23—August 11
The program features：
●College courses (over 200 to choose from), which you attend with college students, other high school students, and professionals from around the world.
●Credits you can transfer to a college in the future.
●The choice to live on campus, commute (走读), or study online.
●The freedom to schedule your days.
For students living on campus, the average cost of attending the program is $11,900, which includes fees for two 4credit courses ($3,050 for each course) or one 8credit course ($6,100), room and meal fees, and a health insurance fee. For those attending as a commuting or online student, the cost ranges from $3,050 to $6,100 depending on the number of courses taken.
Reasons why cellphone signals suddenly go bad
Heavy cellular traffic
Just take a look at those people around you. See if they are doing the same thing as you are: texting or talking on their phones. Once your phone has linked to a tower, you are unlikely to lose your connection, but the more phone traffic there is, the weaker your signal can become.
Building material
The building material of your house, car or workplace is usually the main reason for weaker signals. If you routinely notice service fading in and out as you walk around your home, or if your signal improves when you stand near a window or door, it's likely that your signal is being blocked by the construction material.
Blocking your own antenna
Sure, they were as big as shoe boxes, but they also had antennas on the outside. Today's phones have antennas fixed inside the phone. If you're not careful how you re holding the phone, you can block the antenna, and lose your signal.
Hills and valleys
If you live on one side of a mountain, and the only cellphone tower in your area is on the other, you are not likely to get good reception.
Low battery
If you've been putting off charging your phone battery, you may find yourself with a weak signal when you need it most. Therefore, it may struggle when its battery is low.
A. Avoid talking for a long time on your phone.
B. Geographic features are a common reason for weak signals.
C. Close your eyes and picture the early days of mobile phones.
D. Metal and colored, low-e glass are the two materials most responsible.
E. Your phone needs energy to maintain a connection with a cellphone tower.
F. If so, all those signals are fighting for space on the nearest cellphone tower.
G. Tall trees around your home seldom cause a drop in your cellular reception.
Health advice on hand sanitizers
Antibacterial hand sanitizers (免洗洗手液) are marketed as a good alternative (替代品) when soap and water are not available. Manufacturers say that their sanitizers kill 99. 9 percent of germs (细菌) , but research suggests that this not the case.
How do hand sanitizers work?
Most sanitizers are alcohol-based; they work by removing the outer layer of oil on our skin, then the alcohol kills the bacteria.
However, Barbara Almanza, associate professor at Purdue University, notes that hand sanitizers do not significantly reduce the amount of bacteria, and in some cases, can increase it.
So the question arises, how can manufacturers say sanitizers kill 99. 9 percent of bacteria?
How can manufacturers make the 99. 9 percent claim (声称) ?
Manufacturers test their products on bacteria-tainted surfaces. In this controlled environment, hand sanitizers do kill 99. 9 percent of bacteria. However, the human hand is a lot more complex and goes through a lot of different changes in a day compared to a controlled surface.
These tests allow manufactures to obtain consistent results. But, in reality, how effective are hand sanitizers in killing bacteria in everyday life?
Hand sanitizer VS hand soap and water
Almanza says that soap and water are the best way to clean your hands. Hand sanitizer cannot and should not be a direct replacement.
However, they are a useful alternative. To effectively kill bacteria, studies recommend that people use sanitizers that are at least 60 percent alcohol. Also, sanitizers won't work if you have dirty hands, so wipe them with a tissue or napkin before sanitizing.
What about antibacterial soaps?
Research has shown that regular soap is just as effective as antibacterial soap in reducing bacteria-related illnesses.
In fact, some consumer antibacterial soap may increase some bacteria's resistance to antibiotics (抗生素) , making them more dangerous.
Other studies show that overly clean environments will negatively affect children by preventing their immune (免疫的) system development. Children need to fight off common germs to develop their immune systems.
As a teenager, I hated P.E. lessons. I was not very good at sports, and I hated team sports because I always felt like I was disappointing the rest of the team. During these years, I sometimes felt disconnected from my body, like only my brain was “me” and my body was just a vehicle for carrying my brain around.
When I started university, I decided to try Kung Fu Club. To my surprise, I loved it! In my first year most of us were beginners. I used to go two or three times a week. Because it is not a team sport, I didn’t feel guilty about not being very good. And because it is a combat( 格斗 ) sport, you train in pairs, which means that you get to meet people and talk to them. I also appreciated that the focus of the classes was on getting better at kung fu, rather than exercising to change my body. When I was doing kung fu, my body changed—I got stronger and quicker—but the changes were a side effect of the sport, instead of the goal.
When I moved to Italy this year, I decided to start doing a combat sport again. I joined a local martial arts( 武术 ) club and I love it. We do lots of sparring. I think that sparring is like chess, but much faster and much more fun! If your sparring partner tries to hit you hard with his fist, you have to move quickly to avoid him, block or even catch his arm and then throw him to the mat.
When I was a teenager, I would say I just wasn’t a sporty person and that I just didn’t like sport and never would. Now I think that everyone should try as many sports as possible because I believe there is something out there for everyone! I feel connected to my body and I am happier and have more energy when I have been doing sport.
1 ． Why did the author hate P.E. lessons when he was a teenager? ( 不多于 7 个单词 )
2 ． What club did the author go to when he was at university? ( 不多于 3 个单词 )
3 ． What did the author do after he moved to Italy? ( 不多于 7 个单词 )
4 ． How did the author become a sporty person? ( 不多于 8 个单词 )
我宁愿考不及格，也不愿意考试作弊。(would rather)
Children should learn to be responsible for themselves in order to live a secure future. You can read this article to help your child become responsible.
Power of examples.
We all know that kids are influenced by the actions of elders, especially their parents. 16 Parents should follow good time management skills and should also teach their kids the significance of these skills. 17 Even small things can influence the mind of your child, like turning the lights off when there is no one in the room, or waking up on time for the day's work.
18
You can reward kids with something they like to encourage them to do things willingly. Give your kid small duties like washing clothes and cleaning the garden, etc. , and tell him the importance of doing these duties n his own. 19
Teach him money management.
To prevent your kid from becoming a spendthrift(挥霍者) you should teach him the importance of saving money. Do not splurge (乱花钱) money on your kid and instead, ask him to manage his allowance budget(零花钱预算). If your kid uses up his money quickly, you should teach him to be responsible for his money. 20
A. Teach them to earn money by themselves.
B. This way he will not spend more than he has.
C. Make learning and holding responsibility fun for your kids.
D. You should complete the hard task together with them.
E. Give your child duties and rewards.
F. To make kids more responsible, parents should check their own behaviour.
G. The actions also matter.
--- Can your factory really afford ____ food for the people in the flooded area?
--- I believe we can because we have ____ workers.
A. a number of; plenty of B. a large amount of; the number of
C. plenty of; the number of D. a large amount of; a number of
My friend’s grandfather came to America from a farm in Thailand. After arriving in New York, he went into a cafeteria(自助餐厅) in Manhattan to get something to eat. He sat down at an empty table and waited for someone to take his order. Of course nobody did. Finally, a woman with a big plate full of food came up to him. She sat down opposite him and told him how a cafeteria worked.
“Start out at that end,” she said, “Just go along the line and choose what you want. At the other end they’ll tell you how much you have to pay.”
“I soon learned that’s how everything works in America,” the grandfather told my friend later, “Life’s a cafeteria here. You can get anything you want as long as you want to pay the price. You can even get success, but you’ll never get it if you wait for someone to bring it to you. You have to get up and get it yourself.
21. The grandfather went into a cafeteria to .
A. get something to eat
B. wait for someone
C. meet my friend
D. buy something
22. The woman in the cafeteria might be .
A. a waitress
B. a friend of grandpa’s
C. a customer
D. an assistant
23. What should we do to get food in a cafeteria?
A. Wait for the waiter.
B. Ask someone for help.
C. Sit down at an empty table.
D. Get it ourselves.
24. What can we learn from the grandfather’s words about the life in the US?
A. Get up early and you can succeed.
B. Nobody brings you anything unless you pay the price.
C. Act and get what you want on your own.
D. Waiting is very important.
The Brown Bear
My wife Laura and I were on the beach, with three of our children, taking pictures of shore birds near our home in Alaska when we spotted a bear. The bear was thin and small, moving aimlessly.
Just a few minutes later, I heard my daughter shouting, “Dad! The bear is right behind us!” An agreesive bear will usually rush forward to frighten away its enemy but would suddenly stop at the last minute. This one was silent and its ears pinned back---- the sign (迹象) of an animal that is going in for the kill. And it was a cold April day. The bear behaved abnormally, probably because of hunger
I held my camera tripod (三脚架) in both hands to form a barrier as the bear rushed into me. Its huge head was level with my chest and shoulders, and the tripod stuck across its mouth. It bit down and I found myself supporting its weight. I knew I would not be able to hold it for long.
Even so, this was a fight I had to win: I was all that stood between the bear and my family, who would stand little chance of running faster than a brown bear.
The bear hit at the camera, cutting it off the tripod. I raised my left arm to protect my face; the beast held tightly on the tripod and pressed it into my side. My arm could not move, and I sensed that my bones were going to break.
Drawing back my free hand, I struck the bear as hard as I could for five to six times. The bear opened its mouth and I grasped its fur, trying to push it away. I was actually wrestling (扭打) with the bear at this point. Then, as suddenly as it had begun, the fight ended. The bear moved back toward the forest, before returning for another attack----- The first time I felf panic.
Apparently satisfied that we caused no further threat, the bear moved off, destroying a fence as it went. My arm was injured, but the outcome for us could hardly have been better. I’m proud that my family reminded clear-headed when panic could have led to a very different outcome.
60. The brown bear approached the family in order to _______.
A. catch shore birds B. start an attack
C. protect the children D. set up a barrier for itself
61. The bear finally went away after it _______.
A. felt safe B. got injured
C. found some food D. took away the camera
62. The writer and his family survived mainly due to their ______ .
A. pride B. patience
C. calmness D. cautiousness
