1 . Joshua trees — some of the most unusual and famous plants of the American Southwest — have survived as a species for some 2.5 million years in the Mojave Desert. Now, they may face extinction due to climate change.

In a new study published in the journal Ecosphere, researchers and volunteer scientists surveyed nearly 4,000 trees in southern California’s Joshua Tree National Park to figure out where the oldest trees grew the best during historic periods of extreme heat and drought. Then, the researchers estimated (估算) how many of these Joshua safe areas would survive to the end of the century based on a range of climate change predictions.

The study authors found that if greenhouse gas emissions (排放物) are seriously limited and summer temperatures are limited to an increase of 5.4 degrees Fahrenheit, about 19% of the park’s Joshua tree habitat (栖息地) would survive after the year 2070. If no action is taken to reduce greenhouse gas emissions and summer temperatures rise by 9 degrees Fahrenheit or more, however, only 0.02% of the tree’s habitat would survive to the end of the century, leaving the tree close to extinction.

One way to save the Joshua trees from extinction is to reduce greenhouse gas emissions. However, even if the habitats survive, these trees will still be in danger because of wildfires, which have also been happening more often as the climate warms. According to the researchers, fewer than 10% of Joshua trees survive when wildfires rush through their habitats.

“Removing grass is a way park rangers (护林员) are helping to protect the area from fire today,” Sweet, a plant ecologist at the University of California, said. “By protecting the trees, they’re protecting a host of other native insects and animals that depend on them as well.”

1. Why did the researchers survey some Joshua trees?

A．To predict the number of Joshua trees.

B．To know their past and predict their future.

C．To make sure they will be safe from disasters.

D．To set up more nature reserves for Joshua trees.

2. What would the researchers agree with as for Joshua Tree National Park’s Joshua trees?

A．Their future is in humans’ hand.

B．Their numbers are dropping greatly.

C．They may adapt to rising temperatures.

D．They are suffering most from climate change.

3. What does the last but one paragraph focus on?

A．Another way to save Joshua trees.

B．Another threat Joshua trees may face.

C．The importance of Joshua trees’ habitats.

D．The chance of fire happening to Joshua trees.

4. Which best describes the park rangers’ work of removing grass?

A．Skilled.	B．Challenging.
C．Creative.	D．Worthwhile.

2 . Gardens come in all shapes and sizes.     1     But with a little planning and a few tips, you’ll be growing in no time.

One of the most important things to remember when planning a garden is to grow what you love. This way, you’ll be sure to enjoy the process. You can grow vegetables. If you don’t like vegetables, try fruits or flowers. You can grow a garden to feed yourself, your neighbors, and a family that’s going through a hard time.     2     Find your interest.

Once you decide what type of garden you’d like to start, you’ll need to plan a few things before getting to work.     3     Find a place that is fairly flat and gets good sunlight. After that, it is necessary to pick the right soil. An expert at a gardening store can advise you on the best soil for your needs.

After you have the correct soil, choose your plants. Will you start with seeds or young plants? Growing from seeds is often less expensive. And it’s more satisfying, because you have a chance to watch the growth from seed to plant.     4     There’s a better possibility your plant will survive the environment condition to produce.

    5     I suggest planting right before the start of the growing season so the plants can adapt to the soil. You’ll see them start to produce sooner.

A．Now you’re ready to plant your garden.

B．Starting a new one might seem challenging.

C．But growing from young plants is easier.

D．First, work out where your garden will lie.

E．You’ll be able to plant season after season and try to grow new things.

F．It will help you explore and understand the whole progress of these plants.

G．There are many different things you can grow and many different reasons to grow.