1 . The public nowadays has a misunderstanding of forest fires, believing that fires should be kept out of every type of forest. Many of us can recall Smoky the Bear's famous warning: “Remember, only YOU can prevent forest fires”. However, that's not always the case. Under the right conditions, and when conducted safely, fire can create many environmental benefits as well as help prevent larger, uncontrollable wildfires.
After a forest fire, many wildlife species will move into recently burned areas to feed on these newly available foods. Some reptiles and amphibians such as the pine (松树） snake prefer forests frequently burned by fire. As Herbert Stoddard put it, “One of the most harmful things modern man has done to birds has been his attempt to exclude fire from fire-type pine forests. Within a few years most forests choke up with bushes, lose their prairie-like vegetation (草原般植被） and can no longer support birds dependent on periodic burning for their food supply and proper cover.”
If you are asked to picture the forest floor, what do you see? Pine needles, cones, leaves, branches might come to mind-all sources of fuel. If these fuel sources build up without any type of removal, the 'fuel load' can lead to fires catastrophic to forests and people alike. In contrast, prescribed fire can be used by forest professionals every couple of years to keep forest fuels at an appropriate and manageable level. They can also minimize the spread of pest insects and disease and remove unwanted tree and plant species. Plus, they can create and maintain important wildlife habitats rich in grasses and promote the growth of trees, wildflowers and other various plants.
Many organizations and agencies work to promote fire on the landscape when and where appropriate. Smokey Bear even has an updated warning: “Only You can Prevent Wildfires,” as the Forest Service has over the last few decades developed policies and procedures to include prescribed fire as a management tool, as well as continuing their work to prevent and fight wildfires.
1. Why did the author mention Smoky the Bear's warning?| A．To introduce the topic of the passage. |
| B．To clarify a misunderstood concept. |
| C．To show the significance of fire prevention. |
| D．To raise people's awareness of forest protection. |
| A．Forest bushes. |
| B．Fuel sources. |
| C．Pine forests. |
| D．Periodic burning. |
| A．To put out wildfires. |
| B．To keep the forest balance. |
| C．To remove tree and plant species. |
| D．To keep the fuel rich in the forest. |
| A．One Match Can Start A Forest Fire |
| B．Where There Is Smoke There Is A Fire |
| C．Not All Forest Fires Are Created Equal |
| D．Why Not Keep The Forest Fire Burning |
2 . Until now, scientists haven’t been able to study the new rock on the moon.The new samples from Chang’e 5 will change this. They’re from near Mons Rümker, a volcanic mountain where the rock is thought to be much younger-- about 1 billion years old.
There are a lot of reasons scientists are eager to study this younger rock, one of which is that it could help us more precisely date not only the moon, but many rocky planets and other objects.
Here’s how that works: Scientists date lunar rock by using something called a chronology curve（年代学曲线）, says Jollliff, a scientists at Washington University in St. Louis. Basically, they estimate the age of the rock by counting the number of craters（火山口） in the area the rock comes from; those increase as objects strike the rock over time. To make this estimation, scientists need to match the number of craters to a precise age. Right now, they only have data points for lunar rock that is 3 to billion years old. Modern techniques can date the new sample extremely accurately, and once scientists know its precise age, they can add a valuable data point to their chronology curve. The dating system will also help us more accurately estimate the age of all sorts of objects in space, like rocky planets and other moons.
Another reason scientists are keen to study this young volcanic rock is to find out more about how volcanism works on the moon. Jollliff says that it’s unclear why there was volcanic activity on the moon for such a long period of time. Most of the moon; s volcanic activity, he says, is thought to have occurred 3 or 4 billion years ago, when the moon was still pretty young. But since the moon does not have plate structure, which drives volcanism on Earth, it’s unclear what could have caused much later volcanic activity. “That’s something that you can find out of the samples by studying them in the lab,” Jollliff says.
1. What does the underlined word “this” in paragraph 1 refer to?| A．The fact of being unable to study the new rock. |
| B．The new rock from near Mons Rümker. |
| C．One of the reasons to study the moon;s new rock. |
| D．The study of the moon’s younger rock. |
| A．ensure there was volcanic activity on the moon. |
| B．more precisely date only the moon. |
| C．date lunar rock by using a chronology curve. |
| D．explore how volcanism works on the moon. |
| A．Scientistsare keen to study this young volcanic rock. |
| B．Scientists can’t know why volcanic activity exists on the moon. |
| C．The moon’s volcanic activity occurred 3 or 4 billion years ago. |
| D．It’s clear what could have caused much later volcanic activity. |
| A．How scientists study the younger rock. |
| B．Why the research is important. |
| C．Why the younger rock is worth studying. |
| D．What scientists do to study the younger rock. |
3 . Ian McKenna was in third grade when he learned that many kids at his Austin school weren't getting enough to eat at home. He wanted to help, but local volunteer organizations turned him away, saying he was too young. So he decided to find his own solution. For years, he had been gardening with his mother, and they often distributed their extra vegetables to the neighbors. “Why not give the produce to a soup kitchen? Then I thought, I'm good at gardening," says McKenna, now 16. “Why not plant a garden at school, so that kids in need could take food home?"
McKenna persuaded his school to set aside space for a garden; then he asked the community for donations of seeds and equipment. Other students donated their time. Within months, McKenna's garden was producing lettuces, tomatoes, cucumbers and squash for students and their families. Now, seven years later, McKenna's Giving Garden project has expanded to five area schools in addition to his own backyard garden, and he has provided organic produce, enough for 25,000 meals, to Austin families.
For most of his gardening activities, McKenna wears the same T-shirt in different colors, with his personal motto on it: BE A GOOD HUMAN. To him, that means helping in any way you can, no matter what your age. "Even a smile might change someone's life," he says. “It lets them know that they are important. It can make their day."
When COVID-19 hit the U.S., McKenna redoubled his efforts, cooking up to 100 meals to distribute to the hungry on the weekends. When social distancing meant that volunteers couldn't work on community garden plots, he started offering online classes and a gardening hotline so families could grow at home. While gardening is his core focus, McKenna says he is always looking for new ways to help the hungry.
1. What caused Ian's decision to help the kids in his own way?| A．Being rejected by volunteer groups. | B．Being good at gardening. |
| C．A soup kitchen's support. | D．His mother's suggestions. |
| A．It helps students only. | B．It was started with joint efforts. |
| C．It is funded by schools. | D．It earns great profits every year. |
| A．Where there is a will, there is a way. | B．A small gesture makes a difference. |
| C．One good turn deserves another. | D．Love can break all the barriers. |
| A．Ian McKenna, Growing a Food Bank |
| B．Ian Mckenna, an Experienced Gardener |
| C．Giving Garden Project, an Impossible Mission |
| D．Giving Garden Project, a Universal Solution |
