Some people were eating and drinking in a coffee house. A young woman was sitting alone at a table. She was wearing a beautiful diamond necklace. There was an ugly man at a table not far from her. He was looking at her necklace all the time.

    Suddenly the lights went out. The coffee house was in darkness. The woman started to shout. She was very frightened. A few minutes later the lights came on again. The woman was crying. Her necklace was missing.

    The manager quickly closed all the doors. He telephoned the police. No one could get out of the coffee house. The policemen soon came. The police inspector told his men to search everyone. The necklace was not on anyone. They then searched the whole coffee house. The necklace couldn't be found.

The police inspector then looked at the faces of all the people in the coffee house. He saw the ugly man and looked at the man carefully. He went up to the man and picked up the bowl of soup that was on his table. He then poured the soup into a glass. The necklace fell out. The policemen caught hold of the man and took him away. The young woman was happy to get back her necklace.

    Low-Cost Gifts for Mother's Day

    Gift No. 1

    Offer to be your mother's health friend. Promise to be there for any and all doctor's visits whether a disease or a regular medical check -up. Most mothers always say no need, another set of eyes and ears is always a good idea at a doctor's visit. The best part? This one is free.

    Gift No. 2

    Help your mother organize al1 of her medical records, which include the test results and medical information. Put them all in one place. Be sure to make a list of all of her medicines and what times she takes them. “Having all this information in one place could end up saving your mother's life,” Dr. Marie Savard said.

    Gift No. 3

    Enough sleep is connected to general health conditions. “Buy your mother cotton sheets and comfortable pillows to encourage better sleep.” Savard said. “We know that good sleep is very important to our health.”

    Gift No. 4

    Some gift companies such as Presents for Purpose allow you to pay it forward this Mother's Day by picking gifts in which 10 percent of the price you pay goes to a charity (慈善机构).Gift givers can choose from a wide variety of useful but inexpensive things many of which are “green”—and then choose a meaningful charity from a list. When your mother gets the gift, she will be told that she has helped the chosen charity.

    With its snow-covered mountains and a variety of wildlife, Yellow Stone National Park is one of the scenic treasures of the United States. Located primarily in Wyoming, the park hosts millions of visitors every year. If you plan to travel within the park, keep in mind advice from the National Park Service.

    Seasonal Travel

    Travel varies vastly from season to season. Roads are generally open in the summer except for cases of rock or mud slides, wild fires, accidents or road construction. Early snows in the fall can cause some roads to close temporarily. In the winter almost all roads are closed to motor vehicles, but snowmobiles and other snow vehicles with tracks are allowed. Roads begin to open for the spring by the latter part of April but can close if snowfall continues.

    Driving Time

    Grand Loop is the main road through Yellowstone National Park; it passes by most of the major attractions. These include Old Faithful, Yellowstone Lake and the Grand Canyon of Yellowstone. The maximum speed limit on the Grand Loop is 45 miles per hour, but the speed limit drops during some of the winding and twisting sections of this narrow road. Allow yourself at least two days to fully travel the loop due to the size of the park and being sometimes stuck in heavy traffic.

    Safety Awareness

    Buffalo(水牛)often block the roads in the park as they move through the fields. If a group is traveling across the road you are on  you can either wait for them to pass or find an alternative route. If you get out of your vehicle, the National Park Service says to stay at least 25 yards from any buffalo (and 100 yards or more away from bears and wolves). Buffalo are particularly unpredictable and charge people at speeds up to 30 mph.

    You can take your bicycle on any public roads and routes designed for bikes, but bicycles are not allowed on the park roads which are narrow with few shoulders. Altitudes range from 5, 300 to 8, 860 feet. The National Park Service recommends cyclists wear helmets and noticeable clothing.

    Students perform less well in final exams if smartphones are allowed in class, for non-academic (非学业的) purposes in lectures, a new study in Educational Psychology finds. Students who don't use smartphones themselves but attend lectures where their use is acceptable also do worse, suggesting that smartphone use damages the group learning environment.

    Researchers from Rutgers University in the US performed an in-class experiment to lest whether dividing attention between smartphones and the lecturer during the class affected students' performance in within-lecture tests and a final exam. 118 students at Rutgers University took part in the experiment during one term of their course. Smartphones were not allowed in half of the lectures and allowed in the other half. When smartphones were allowed, students were asked to record whether they had used them for non-academic purposes during the lecture.

    The study found that having a smartphone didn't lower students' scores in comprehension tests within lectures, but it did lower scores in the final exam by at least 5%, or half a grade. This finding shows for the first time that the main effect of divided attention in the classroom is on the length of time in keeping memory, with fewer things of a study task later remembered. In addition, when the use of smartphones was allowed in class, performance was also poorer for students who did not use them as well as for those who did.

    The study's lead author, Professor Arnold Glass, added: "These findings should alarm students and teachers that dividing attention is having a not obvious but harmful effect that is damaging their exam performance and final grade. To help manage the use of smartphones in the classroom, teachers should explain to students the alarming effect—not only for themselves, but for the whole class."

    This is the first-ever study in an actual classroom showing a relationship between losing attention from smartphones and exam performance. However, more researches are required to see how students are affected by using smartphones after school.

    Which kind of diamond is better for the environment and the world we live in: a diamond from a traditional mine or one made in a laboratory?

    Some recent reports suggest the answer may not be so clear. At the very least, these reports provide evidence of tensions between two different sectors of the diamond industry.

    Lab -grown diamond companies say they are more ethical and cause less harm to Earth's environment. The traditional diamond sector notes that its businesses help the communities where they operate mines. It says they provide jobs, help build roads and other infrastructure and make investments in conservation.

    Some companies, such as De Beers, work on both sides. De Beers sells natural and man-made diamonds. In the United States, the Federal Trade Commission(FTC) investigates reports of deceptive, or misleading, advertising. In April, the commission sent warning letters to eight lab-grown diamond companies. One of the FTC's concerns was the use of the word 'eco-friendly', and similar terms, to describe diamonds made in a laboratory. The lab-grown process requires very high temperatures and uses a lot of energy. Trucost is a company that estimates the costs of using natural resources. Asked by the Diamond Producers Association to study the issue, Trucost found the carbon intensity of natural diamonds was lower than lab-grown diamonds.

    The Trucost report did note that diamond miners should reduce their effect on the environment by using more renewable energy, such as wind power and sunlight.