Olivia Ries was just seven years old when she and her eight-year-old brother Carter adopted a cheetah（猎豹） in South Africa. 

"When my sister and I first learned back in 2009 that species like the cheetah may be extinct in the wild by the time we have kids，it scared us. We knew we had to do something to help them，"says Carter. "There are so many people （young and old alike）who just don't know what is happening to so many species，just like we didn't. Olivia and I want to make sure we reach as many people around the world as possible and help them to understand how serious the situation really is."

To do that ， the kids started One More Generation（OMG），an organization with the motto："Preserving endangered species for one more generation and beyond."

Now，many years later，Olivia and Carter have traveled all over the world spreading their message. They've been interviewed on national television，participated in marches and fundraisers and won awards for their work. In 2015，they were invited to Vietnam by the United States Embassy to participate in a programme to save rhinos. All that they've accomplished for animals and the environment is much too long to list!

"Our number one message to everyone we meet is‘Remember，anyone can make a difference...if we can，you can too'，"says Olivia."We want all people to understand that what Carter and I are doing is not necessarily something special；it is something that we all should be doing. You can start small by simply adopting an animal. Do some research on the species you are interested in，and find a good organization offering adoptions. My brother and I take our birthday money and allowance money and adopt animals all the time. "

A wonderful experience happened to me this Saturday on my way to a mall. Two children ran towards mebottles in their hands，asking if I wanted to have bottled water. It was so （surprise）that I was unsure whether this was for real. I wondered if they （do）fund-raising. I asked them where（they）parents were and how much a bottle of water was. Then two adult women came to me and explained what the children were doing，"We are teaching the children （give）without getting anything in return."What a great idea!

 exchange of ideas opened up between me，the mothers and the children. We were no longer strangers to each other. We were having such a great time chatting. I felt very pleased，（end）up helping them give away the rest of the bottled water. 

One young lady was so （thank） that she said it was the best thing happened to her all day since she had a"bad"day at work. A couple accepted the water （happy）and kept on thanking us. After all was done，the children and I gave each other a high five. I really had great fun that day.

Manfred Steiner had a successful and productive career as a doctor, helping generations of medical students learn about hematology(血液学). But all along, he had a strong feeling that he should be doing something else: studying physics. At age 89, he has finally realized that dream, earning his PhD in physics from Brown University.

"I am really on top of the world. It's my third doctoral degree, but this is the one I really cherish a lot. made it—and made it at this age," said Steiner in an interview with NPR. "I always had this dream: Someday I'd like to become a physicist."

Steiner grew up in Vienna. When he was just a teenager, he was fascinated with physics. However, persuaded by his parents, he decided to pursue a medical career instead. But during his studies in Vienna, physics still tugged at him. "When I was a medical student, I used to go to the institute of physics, which was very close to the medical school," he said, "and listen to some lectures about physics there."

When Steiner moved permanently to the US from Vienna, he focused on medicine and hematology, training at Tufts University and MIT. He then became a professor at Brown and led the hematology section in the university's medical school.

It was only after Steiner retired from his career in medicine in 2000 that he was finally able to scratch the physics itch(痒). He started taking classes at MIT. "I had to do a lot of physics classes at MIT before being allowed to start graduate studies," he said.

Steiner worked slowly—he's a grandfather who likes to spend time with his family, and health problems have been a concern—but the credits kept piling up. And before long, Steiner was eyeing yet another PhD.

"You know, it took a long time," he said. "There were very serious health problems in between. But fortunately, I' m here now and I've overcome these problems. "