Chester Greenwood was freezing. It was in 1873 and Chester was _________ a new pair of ice skates. The 15-year-old was getting _________because he couldn't keep his ears _________ or protect them from the bitter cold. He tried wrapping a _________around his head but it was too _________and itchy. Besides，who can _________ with a scarf tied around their heads？

To _________his problem，Chester made two ear-shaped rings from wire and asked his grandmother to sew beaver fur and cloth _________them. Over the years his new invention，the earmuff，improved-a steel band was added，so it became _________and tiny chains were added so it would ____________in pockets. Finally Chester had his own ____________，Greenwood's Ear Protector Factory. He made a ____________providing ear protectors for the US soldiers during World War I.

Chester ____________over 100 products during his lifetime. Some of them are the wide bottom kettle，the spring steel rack，the folding bed，the shock absorber（减震器）that ____________today's airplane landing gear（起落架）and bearings to keep ____________from being pulled off，ensuring that they touch the ground safely. The Smithsonian Institution named Chester one of America's 15 ____________ inventors.

The town of Farmington, Maine, where Chester was born, has an annual holiday to ____________the inventor. December 21st is Chester Greenwood Day and people all over the state of Maine ____________in the celebration. Farmington has a parade on the first Saturday in December and everyone from kids to old people shows up ____________earmuffs. He invented over 100 products ____________Chester will always be remembered for inventing the earmuffs when he was 15.

   In the modern world，there is an unfortunate tendency to value profit over intelligence. People may know a practice is harmful，but continue to do it anyway because it produces an in-demand product. Fortunately，there are inventors who work tirelessly to develop more responsible solutions. Sally Fox is one such individual.

Before Fox's invention of Foxfibre cotton，naturally colored cotton could only be spun（纺线）by hand，which was such a long and laborious process that businesses chose to take white cotton，bleach（漂白）it，dye it and spin it on a machine. This produced the colored fabrics people wanted，but also created a lot of pollution through the bleaching and dying processes. Sadly，there weren't really any practical choices available until Sally Fox came along in the late 1980s and revolutionized the industry.

While working as a pollinator（传花粉者）for a cotton breeder looking to develop more pest-resistant plants，Fox began breeding brown and green cotton，picking out the best seeds that produced the longest fibres and replanting them year after year. Finally，she created two kinds of colored cotton that could be spun on a machine，and she purchased a small lot of land to grow them. Sally even received Plant Variety Protection Certificates for the new cotton.

By the early 1990s，Sally Fox had had a 10-million-dollar business that produced naturally colored cotton for major companies like Levi's，Esprit，Land's End and L. L. Bean. It was a more environmentally friendly product that was also turning a profit. After globalization forced most of the spinning mills（工厂）to South America and Southeast Asia，Fox's business took a hit，but she continues to make new naturally colored cotton to this day. Each new color takes about 10 years to produce—but，for Sally Fox，the patience is worth the payoff.

   James T. Green thought he was having a panic attack.

He took a break from work to walk around the block during a stressful day, and noticed he felt out of breath climbing up a small hill. That wasn’t normal, Green thought. He had become a regular biker in recent months and wasn’t exactly out of shape. He sat down at his desk, and looked at the Apple Watch on his wrist. His heart rate was through the roof, and the Heart Watch app he was using to check his pulse was flashing warnings. Maybe it was something more serious, he thought.

Although he had blood clots（血栓）in his lungs a few years back, he had been taking medication, and doctors said that it was an unusual condition for someone in their mid-20s. Still, the symptoms this time were much less severe, and he was feeling stressed, so his mind didn’t automatically jump to blood clots. Green’s doctor told him it sounded like anxiety. But then he showed her his heart rate recorded by the Apple Watch.

“This is my normal heart rate,” Green told her, pointing to the graph in the app. “This is where my heart is now. There’s something wrong.”

The doctor ordered a CT scan. The blood clots in his left lung had returned. An ambulance rushed Green to the emergency room, where he was pumped full of blood thinners（血液稀释剂）. He didn’t need surgery this time, but doctors told him that if he had waited, a clot could have killed him.

Green isn’t the only person who has discovered a serious health condition after seeing heart-rate data on a smartwatch. And he won’t be the last. Currently, smartwatches from Apple and others can tell you your heart rate and track your workouts. But these companies want to go beyond the basics by developing ways to tell you when something is wrong. In fact, it’s already happening.

   Researchers are placing robotic dogs in the homes of lonely old people to determine whether they can improve the quality of life for humans. Alan Beck, an expert in the human-animal relationship, and Nancy Edwards, a professor of nursing, are leading the animal-assisted study concerning the influence of robotic dogs on old people’s depression, physical activity, and life satisfaction. “No one will argue that an older person is better off being more active, challenged, or stimulated (刺激), ”Edwards points out. “The problem is how we promote that, especially for those without friends or help. A robotic dog could be a solution.”

In the study, the robotic dogs, called AIBO, are placed for six weeks in the houses of some old people who live alone. Before placing AIBO in the home, researchers will collect data for six weeks. These old people will keep a diary to note their feelings and activities before and after AIBO being placed. Then, the researchers will study the data to determine if it has inspired any changes in the life of its owner.

“I talk to it all the time, and it responds (回应) to my voice,” says a seventy-year-old lady. “When I’m watching TV, it’ll stay in my arms until it wants to go down. It has a mind of its own.”

The AIBOs respond to certain orders. The researchers say they have some advantages over live dogs, especially for old people. Often the elderly are disabled and cannot care for an animal by walking it or playing with it. A robotic dog removes exercise and feeding concerns.

“At the beginning, it was believed that no one would relate to the robotic dog because it is metal and not furry,” Beck says. “But it’s amazing how quickly we have given up that belief.”

“Hopefully, down the road, these robotic pets could become a more valuable health helper. They will record their masters’ blood pressure, oxygen levels, or heart rhythms. AIBOs may even one day have games that can help stimulate older people’s minds.”