Frederick Banting hated school. Having grown up on a farm near Alliston, Ontario, Fred was a good worker but felt uncomfortable and unaccepted in a town school. After graduation, he began studies to become a minister. When that did not go well, he changed his goal to medicine. World War I arrived, and the great need for field medics (救护人员) resulted in the early graduation of Fred. After the war, the young Canadian doctor returned home to set up his practice. Just then he began to focus on articles on diabetes (糖尿病), a disease that had claimed the life of a neighbour’s child.

To solve the problem of this disease, Fred approached Dr. J. J. R. Macleod at the University of Toronto and eventually convinced Dr. Macleod to support him. In 1920, Fred happily entered a poorly equipped laboratory and was given a young assistant named Charles Best. Fred and Charles worked day and night, but early results in producing the hormone (激素) preparation they called insulin (胰岛素) were discouraging. Many of the animals they treated died. Finally one animal survived for several weeks. The team appeared to be finally getting somewhere, and it was time to move on to human subjects. Before treating human patients, however, Fred and Charles tested the safety of their insulin each other. Their tests were a triumph.

The first patient to be treated was a fourteen-year-old boy named Leonard. The year was 1921. The poor boy weighed only seventy-five pounds, and he was barely alive. But the new insulin treatment administered by Fred and Charles was a great success. Leonard gained weight, and his health dramatically improved.

In 1923, the Nobel Prize in medicine was awarded jointly to Canadian doctors Frederick Banting and J. J. R. Macleod. Fred could have made himself a millionaire with his discovery. Instead, he sold his patent for the production of insulin to the University of Toronto-for one dollar-so that the drug could be marketed cheaply and thousands of lives could be saved and improved. Thanks to Fred, diabetics are able to live normal lives where before it was impossible.

Merle Liivand was born in Estonia. As a child, she had health problems, and began swimming to help her lungs get stronger. She was soon taking part in open water swimming contests, sometimes even in icy water. In 2017 and 2019, she represented Estonia at the World Aquatics Championships.

Eleven years ago, Ms. Merle moved to Miami, Florida. In one training session, she nearly wound up swallowing some plastic floating in the sea. That experience made her think of all the sea animals who faced similar pollution every day. She began swimming with a special single swimming fin(鳍状物) attached to both of her feet. This rubbery “monofin” allows her to swim by kicking both of her legs together. “Swimming with the monofin without using my arms is similar to how dolphins and sea animals swim,” says Ms. Merle. She believes that swimming with a monofin “sends a bigger message”.

Ms. Merle first set the world record for swimming with a monofin in 2019, when she swam 10 kilometers off the coast of California. In 2020, she broke the record again by swimming 20. 6 kilometers, this time in Miami, Florida.

Last year, she set a new Guinness World Record by swimming 30 kilometers, again in Florida. Even though it took her 9 hours and 19 minutes to set that record, Ms. Merle says she knew she could go farther. So for the last year, Ms. Merle has been getting up at 4 every morning, putting on her monofin and going swimming.

On May 7, Ms. Merle broke the record once more, this time swimming the length of a full marathon. It took her 11 hours and 54 seconds to swim 42.2 kilometers.

To keep her energy up, a friend followed her in a kayak and gave her food and water from time to time. Along the way, Ms. Merle picked up all the trash she found and put it in the kayak. By the end of her marathon, the kayak held three bags full of trash.

George Washington Carver, who was born a slave in 1861, became one of America’s greatest scientists in the field of agriculture. His discoveries changed farming in the South of the United States. A quiet and kind man, he could have become rich from his discoveries but he preferred “to be of the greatest good to the greatest number of my people.”

George’s mother was a slave, but soon after he was born, he and his brother lost their mother and became orphans. They were raised by Moses and Susan Carver, who were their owners. Slaves took the names of their owners, so George Washington’s last name was Carver, too. In 1865, there were no longer slaves in the United States, but George and his brother continued to live with the Carvers. The Carvers gave him as much of an education as they could. At age 12, George left the Carvers to start life on his own.

For the next 12 years, he worked whenever he could and went to school whenever he could. He managed to finish high school and won a scholarship to go to Highland University. However, when he appeared at the university, they refused to admit him because he was black. This did not stop Carver. He continued to work and save money. Eventually, he went to Simpson College in 1890 to study painting and paid for his school by ironing clothes for other students. Soon, he realized he could not support himself as an artist and decided to study agriculture instead.

In 1891, he was accepted at Iowa Agricultural College. He was the only black student at the college, and as usual he supported himself by doing small jobs. He amazed everyone with his special work with plants. After he graduated, the college asked him to stay on as an instructor because his work with plants and chemistry was so outstanding. So Carver stayed on and taught, but he continued his research with plants while he was teaching.

One day he received a letter from Booker T. Washington, who was the most respected black educator in the country. Washington asked him to work at the Tuskegee Institute, a black agricultural school in Alabama. Tuskegee was a poor black school that could not give Carver a laboratory or a high salary, but Carver decided to go there.

In 1896, Carver started to teach and do research with plants at the Tuskegee Institute. He taught classes on agriculture, and through his experiments he found new ways to help the poor, struggling farmers of the South. Here, farmers had been growing cotton, which wore out the soil. He showed farmers how to plant different crops like peanuts to make the soil richer. After a while, farmers did what he said and were growing more and more peanuts. They were now making more money from peanuts than from cotton.

Carver developed many uses for the peanut. In fact, he found more than 300 uses for the peanut, and he became known as the “peanut man.” He received many prizes and awards for his work. He gave lectures about the uses of peanuts all over the United States and even spoke to Congress about peanuts in 1921. Meanwhile, Carver began to experiment with the sweet potato and discovered more than 100 products that could be made from it, including glue for postage stamps.

By the 1930s, Carver had become famous all over the country and the world. He visited the Prince of Sweden and the British Prince of Wales. Thomas Edison asked Carver to work for him at a salary of more than $100,000 a year. The car manufacturer Henry Ford also made him a generous offer. But Carver was not interested in money; he stayed on at the Tuskegee Institute with a monthly salary of $125.

In 1940, he gave all his life savings of $33,000 to the George Washington Carver Foundation to provide opportunities for African Americans to study in his field, because for Carver, “Education is the key to unlocking the golden door of freedom….” Carver died in 1943.