Forest fires happen in summer when it hasn’t rained for a long time and everything is very dry. For many years, people have thought of fires as disasters that     16     the forest. The science of fire ecology(生态学) studies the connection between fire, plants, and animals in forest fires. Scientists say that the fire is also an important part of the life     17     of a forest. With every fire, the forest is born again.

Forest fires often start when lightning strikes a tree, but people can also cause forest fires. Sometimes they don’t know what they did, and it happens by     18    . But other times it’s done on purpose. Once a fire starts, it     19     burns away the dry leaves and branches. The fire also gets rid of overgrown plants, fallen leaves, and bacteria in the soil that cause diseases. Plants on the forest floor receive more space and sunlight to grow, so they can grow and make seeds quickly.

When a fire starts in a forest, every creature(动物) tries to     20    . Birds fly away and mammals usually run away. Small creatures (such as frogs, mice, and insects) hide underground or under rocks.

Some of the weaker animals die, but many     21    . The animals that don’t die in the fire are the strongest. After a fire, some animals that may not be     22     to the forest come to feed on the bodies of dead animals. There are lots of things for animals to eat in a burned forest. Animals soon go back to their homes in the forest and plants start growing again.

Now, according to fire ecology studies, it’s possible for people to see forest fires as natural     23    . Hundreds of species of plants and animals live together in forests.

Do you like to try something new? Do you always try hard when you meet with problems? Here are four reasons for young people to try hard.

® It helps us to do well.

We often look at people who are successful and wish we could be like them. Perhaps we think these people do well because they have a special talent or are clever or rich or even just l    51    .

Having money, fortune or talent is almost never the main or only reason that people do well. Trying hard is sometimes even more important than any of those. People who rely only on their talent and do not work hard r    52     succeed.

® It helps us to try new things.

Sometimes we can be a bit scared of trying new things. We are afraid we will l    53     silly if we can’t do it properly. This can prevent us from giving new things a chance or pushing o    54     forward in something we already do. If we make up our minds to try hard at the new activity and give it our best shot, we could discover that it’s something we are getting to loving doing.

® It teaches us how to solve problems.

Trying hard is not something we have to do a    55    . We can always ask for help and if we have a big problem, the best thing is to ask a parent or a teacher. Of course, we can solve problems on our own if we try hard.

Trying hard means putting an e    56     in even if we don’t get things right the first time. But remember, we learn from our failures. We learn we can try doing it another way.

® It makes us feel proud.

Trying hard gives us a feeling of achievement. When we try hard and we succeed, it makes us feel confident about our a    57    . It teaches us that we can get better at things. It helps us behave well because we learn that we are capable (有能力的) of achieving things.

“Hey, Dan, you look like the unhappiest guy in the world!” said Ella, as they volunteered as ushers (引座员) at the theater.

“Yeah,” Dan replied, trying to smile. “Remember the role you helped me practise last week? Well, I failed again.” “Oh, Dan, keep practicing! You’ll be on the other side of the curtain one day,” said Ella.

Dan kept practicing. He sang day and night. He sang everywhere he went! He wanted to be an opera singer more than anything else in the world. He volunteered at the theater on Saturdays, but he needed to start earning money to pay for singing and Italian lessons.

One day Dan saw an ad asking for bicycle delivery men. Then he began his new job delivering food to customers all over the city. Dan thought it was very rewarding making hungry people happy, but he had a problem. He wasn’t getting enough time to practice singing. Then one day, he had a great idea.

Dan arrived at 52nd Street. “I have your burgers and your fries,” he sang. “I have your soda and your le-mon-ade...” The customers were very surprised! When he finished, they clapped and gave him a nice big tip.

One night, there was an order for lobster soup to a beautiful, big house on the river. Dan rang the bell, took a deep breath and sang, “I have your lovely lobster soup. It smells delicious to me-e-e...”

The door opened slowly and a well-dressed woman appeared. She took the soup, then closed the door, with no tips at all.

A few days later, Dan received a text inviting him to the Opera House.

At the Opera House, a woman greeted Dan. It was the lady who Dan delivered lobster soup to last week. She said, “I am Antonia Allegro, the director here. I’d like to invite you to our next opera. This is your first rehearsal(排练). You’ll practice today. At my house last week, you had one of the most beautiful voices in the world! You’re so talented! Congratulations. Welcome to the show!”

Dan’s first opera performance was in front of thousands of people, and he didn’t sing about burgers or fries or lemonade!