4 . A set of tusks (象牙) is usually an advantage for elephants, allowing them to dig for water, peel bark for food and defend themselves. But during episodes of intense ivory poaching, those big tusks may invite danger. Now researchers have figured out how years of civil war and poaching in Mozambique have led to a greater number of elephants that will never develop tusks.

During the conflict from 1977 to 1992, fighters on both sides killed elephants for ivory to finance war efforts. In the region, around 90% of the elephants were killed. The survivors were likely to share a key characteristic: half the females were naturally tuskless - they simply never developed tusks - while before the war, less than a fifth lacked tusks.

After the war, those tuskless surviving females passed on their genes with expected,as well as surprising, results. About half their daughters were tuskless. More confusing, two-thirds of their offspring (后代) were female. “The years of unrest changed the evolution in that population,” said evolutionary biologist Shane Staton.

Most people think of evolution as something that proceeds slowly, but humans can hit the accelerator. “When we think about natural selection,we think about it happening over hundreds, or thousands of years,” said Samuel Wasser, a conservation biologist at the University of Washington. “The fact that this dramatic selection for tusklessness happened over 15 years is one of the most astonishing findings.”

Now the scientists are studying what more tuskless elephants means for the species and its environment. “If an elephant doesn’t have the tool to peel bark from trees, then what chain reaction will happen?”

5 . More than a decade ago, while pursuing a hotel management degree in Switzerland, I had to move to Zurich for a six-month internship(实习). The hotel didn’t offer _________ to its staff, so I had to find my own.

It was a difficult task, as Zurich is a(n) _________ city to live in, but I found a tiny room that suited my tight budget. I soon became familiar with the building _________ , among them a father and son singing group from Lahore, Pakistan. Their warm _________ made me feel as if I had known them for ages. When I _________ them I was from Amritsar, India, they seemed more delighted still. “We are from different _________ , but the same highland. If you _________ anything, we are there for you,” they said. True to their word, they _________ food, cheered me when I got homesick and gave me discount cards to help _________ money.

__________ , my internship was extended by 15 days. My rental __________ , however, was up and once again I had nowhere to __________ . My Lahore neighbors invited me to move in with then the moment they __________ my troubles. A manager at the hotel was able to arrange a(n) __________ for me that day, but just the way this family opened up their home to me left my heart so full of __________ and respect.

6 . I remember, when I was growing up, that my mom would tell me stories about the kind acts my dad had done. One day, my dad met a close, long time friend of his in the doowntown area. They talked for a while and his friend________that he didn’t have money for________home. My dad gave him the________money he had, which was for his own train, so he just________home.

I also________these kind acts in our home. Dad would let me and my two younger brothers eat first but he would eat after us. He would________whatever was________on the table. I remember the days when his older brother would sometimes come to our house and________money for his kid’s allowance(零花钱)in school and my dad would give him some. And when it was our time to ask for allowance he would tell us that he had no more money and we should ask our mom.

Dad was a________man and even after his death, there were many people who told me kind________that my dad had done for them, like________them food. He even________to help someone fix his roof and buy him a water pump when he had the money.

In my________life, I never met a man like my dad. For me, he was the kindest, most selfless man on Earth. He would always give________when he could and he gave it with a(n)________heart.

7 . When Paul Greenberg’s son turned 12, he was asking for a smartphone of his own. He challenged Greenberg’s reasons for why it wasn’t a good idea, pointing out his dad’s own addiction to his phone. That’s when Greenberg decided to replace his smartphone with an old-fashioned flip phone and focus on spending time with his son.

Greenberg ended up writing a delightful book about the transition, called “Goodbye Phone, Hello World: 60 Ways to Disconnect from Tech and Reconnect to Joy”—but it’s different from what you might expect. It’s not an essay on the evils(罪恶)of technology, but a brief, and practical guide on how to live without a smart phone.

The book is divided into chapters that explore the various aspects of your life that will improve when you reallocate your time, such as finding a sense of purpose, strengthening mind and body, building better relationships with friends, family, and lovers, and healing the environment. But first, it opens with a message that our screen addiction is not so much a result of weakness, but rather a carefully invented plan by many computer scientists far more knowledgeable than we are about our own brains and nature.

“I wanted to tell my son that people aren’t addicted to screens because they’re lazy, but instead because billions of dollars have been invested to make this outcome unavoidable. When you look into your phone, you think it’s just your two eyes looking at a screen. What’s really happening is that 10, 000 programmers’ eyes are looking back at you, following you, tailoring your environment so that you’ll keep looking.”

“However, you can quit, refuse to play the game; and when you do, doors of opportunity open all around.”

This book is a pleasure to read. Its briefness is purposely suited to people who have lost their attention span(持续时间), but wish to regain it. I know that when my kids get home from school later today, they won’t see me on my phone. I’ll leave it inside and take them out to play Frisbee.

When Jonah Larson was 5 years old, he found a crochet hook (钩针) in his aunt's bag. He never heard of crochet(钩针编织), a craft similar to knitting, but with the help of     1     (lesson) online, he taught     2     (he)crochet. He started his first project—a small dishcloth     3     turned out great, so he moved on to more projects.

To share his passion for crochet, Jonah started to post his video     4     the Internet. He opened an online store and named it Jonah's Hands, selling crochet kits and books. As his audience grew, Jonah set his sights a little higher. “I saw how crochet inspires lots of people, ”he said. “I wondered whether I could use crochet     5     (change)the world. ”

Jonah     6     (decide)to use the profits from Jonah's Hands to buy books for a school in Teza Gerba of Ethiopia, the African country he was     7     (original)from. “The kids in the village where I was born live in very poor conditions, ”he said. “They don't always have opportunities for the same     8     (educate) as I've had. ”

With the help of his mom, Jonah also launched a campaign to raise money to buy books for the school in Teza Gerba. Jonah was very happy after     9     (raise)almost $35, 000 - enough for not just books but also to build     10     entire library.