I am peter Hodes ,a volunteer stem courier. Since March 2012, I've done 89 trips of those , 51 have been abroad, I have 42 hours to carry stem cells（干细胞）in my little box because I've got two ice packs and that's how long they last, in all, from the time the stem cells are harvested from a donor(捐献者) to the time they can be implanted in the patient, we've got 72 hours at most, So I am always conscious of time.

I had one trip last year where I was caught by a hurricane in America. I picked up the stem cells in Providence, Rhode Island, and was meant to fly to Washington then back to London. But when I arrived at the check-in desk at Providence, the lady on the desk said: “Well, I'm really sorry, I've got some bad news for you-there are no fights from Washington.” So I took my box and put it on the desk and I said: “In this box are some stem cells that are urgently needed for a patient-please, please, you've got to get me back to the United Kingdom.” She just dropped everything. She arranged for a flight on a small plane to be held for mere-routed(改道)me through Newark and got me back to the UK even earlier than originally scheduled.

For thiscourier job, you're consciously aware than that box you're got something that is potentially going to save somebody's life.

    The sharing economy has grown in recent years to include everything from apartment sharing to car sharing to community tool sharing. Since 2009, a new form of sharing economy has been appearing in neighborhoods throughout the US and around the world— Little Free Library. The libraries are boxes placed in neighborhoods from which residents can withdraw (取出) and deposit (存入) books. Little Free Libraries come in all shapes and sizes. Some libraries also have themes, focusing on books for children, adults, or tour guides.

    In 2009, Tod Bol built the first Little Free Library as a gift to his mother, who was a devoted reader. When he saw the people of his community gathering around it, exchanging conversation as well as books, he knew he wanted to take his simple idea further. “I think Little Free Libraries open the door to conversations we want to have with each other,” Bol said.

    Since then, his idea has become a movement, spreading from state to state and country to country. According to Little FreeLibrary.org, there are now 18,000 of the little structures around the world, located in each of the 50 US states and 70 countries in Europe, Africa and Asia.

    The Internet has helped to spread Little Free Libraries. But an Atlantic article says the little structures serve as a cure for a world of e-reader downloads. The little wooden boxes are refreshingly physical and human. For many people, the sense of discovery is Little Free Libraries' main appeal. “A girl walking home from school might pick up a graphic novel that gets her excited about reading; a man on his way to the bus stop might find a volume of poetry that changes his outlook on life,” says the Atlantic article. “Every book is a potential source of inspiration”.

Day 1

    I first heard of “Show Racism (种族歧视) the Red Card” when my friend Jill asked me to support their work. Basically, it's an organization which uses professional (职业的) footballers to help fight racism in sport and society. A few weeks later, he asked me if I wanted to do a bit more for them. I thought he probably meant for me to give money or do some voluntary work. But then he told me that a group of about 20 people were getting sponsored (赞助) to play the highest ever game of rugby (橄榄球) at 5,140 meters on Mount Everest.

Day 4

    We're making our way up to the base camp — that's where most climbers start their final climb to the top — and then, we'll play our game. Today we started out at 8 am. We had to cross three suspension bridges (悬索桥). One of them was so high that you couldn't see the bottom. Then we walked through some beautiful forest areas before we started a two-hour uphill hike to Namche Bazaar.

Day 10

    Base camp is basically just a lot of stones and tents. The walk up was really exhausting. Maybe if I was fitter, I wouldn't find this so hard, but then it was not just me — all of us got very short of breath.

Day 11

    Today we played our game. It was supposed to be a “friendly” game, and last night, we had agreed we'd just walk and not run. However, it was a really heated game and two players were even sent off. We only played for 14 minutes. I think someone would have got hurt if we'd played any longer! My team won and I scored the last try! Of course, none of this matters. What's really important is that we did it and we've raised a load of money.

    Chimps will cooperate in certain ways, like gathering in war parties to protect their territory. But beyond the minimum requirements as social beings, they have little instinct to help one another. Chimps in the wild seek food for themselves. Even chimp mothers regularly decline to share food with their children, who are able from a young age to gather their own food.

In the laboratory, chimps don't naturally share food either. If a chimp is put in a cage where he can pull in one plate of food for himself or, with no great effort, a plate that also provides food for a neighbor to the next cage, he will pull at random —he just doesn't care whether his neighbor gets fed or not. Chimps are truly selfish.

    Human children, on the other hand are extremely cooperative. From the earliest ages, they decide to help others, to share information and to participate in achieving common goals. The psychologist Michael Tomasello has studied this cooperativeness in a series of experiments with very young children. He finds that if babies aged 18 months see an unrelated adult with hands full trying to open a door, almost all will immediately try to help.

    There are several reasons to believe that the urges to help, inform and share are not taught .but naturally possessed in young children. One is that these instincts appear at a very young age before most parents have started to train children to behave socially. Another is that the helping behaviors are not improved if the children are rewarded. A third reason is that social intelligence develops in children before their general cognitive (认知的) skills, at least when compared with chimps. In tests conducted by Tomasello, the children did no better than the chimps on the physical world tests, but were considerably better at understanding the social world.

    The core of what children's minds have and chimps' don't is what Tomasello calls shared intentionality. Part of this ability is that they can infer what others know or are thinking. But beyond that, even very young children want to be part of a shared purpose. They actively seek to be part of a “we”, a group that intends to work toward a shared goal.

    My daughter Alisa was born blind in her right eye and was bullied (欺侮）pretty severely in school. So I quitted my job as a babysitter and then schooled my daughter heart and soul at home.

    A year ago a boy of 14 befriended my daughter on Facebook after reading something Alisa wrote about bullying. Today he messaged her and asked if she would like six tickets to a Colorado Rockies baseball game. They have never met in person but she said, “Sure! That would be great.”

    Then I received a call from his mother explaining why her son had chosen my daughter. She said he thought my daughter deserved them because of all the good she does in the community. Her son, she explained, had experienced a similar situation and was also home schooled.

    What she said is true. Now my daughter Alisa continues to teach groups of girls in trouble in our community how to look within themselves for the positive and how to be their own person.

    Everything taken into consideration, we decided to meet the mother and the boy at a local bike shop. After meeting, the boy approached my car and my daughter gave him a hug and thanked him for his generosity. She told him that she had never been to a baseball game and that she was going to take her entire family, including myself, her dad, little sister, her cousin and an aunt who has brain cancer.

    We all thanked one another, got in our car, and went our way. As we drove home my daughter opened the envelope. Inside it were the tickets and ＄100 each to buy hot dogs, pay for parking and not have any worries but a great time.

    My daughter has always been the giver and now she and our family are the receivers and I can not tell you how incredibly honored we feel to be on the other end. What an incredible young man to have such a kind idea.

    Is it wrong—either grammatically or in terms of style—to mix the simple past tense with the past perfect in one sentence? To give an example, the following seems a bit heavy and awkward to me: "There had been a time when she had been happier.' I prefer: 'There had been a time when she was happier.' Any thoughts?

—ALEX

I think the second version is the correct one—it's shorter and clearer. Rather than focusing on tenses, focus on the clean, short sentence. If something seems heavy and awkward to you, the writer—then it probably is. Always short sentences.

—DIANA

    I have constructed texts for a range of children's picture books all based on working profession: bus driver, postman, footballer, cleaner, teacher, policeman to list a few. I've listed about thirty professions so far. I thought of titling them as Mr Bus Driver, Mr Postman and so on. Would I be infringing (侵权) the Mr Men titles if I did or should I think of something else?

—RAJIV

    The Mr Men stories are based on characteristics, not on jobs—Mr Lazy, Mr Noisy, etc—so they bear no relation to your projects. However, you will come under fire from gender equality supporters—every job you list could equally be done by a woman. No teacher and few parents would find work useful if it implies that all professions are open only to men. I advise you to look at modern children's books in a library or bookshop.

—DIANA