1 . Sunflowers are huge plants with bright yellow flowers. They have a long history in North America. There is evidence that they were used for food and for medicine by Native Americans beginning around 1000 B. C. The seeds from sunflowers were likely brought to Europe by Spanish explorers around the late 16th century. Over time, they found their way to Eastern Europe. Today, Ukraine is the world’s leading producer of the plants. Sunflowers are grown for their seeds and to make oil.
If you start growing sunflowers from seeds, put them in room-temperature water for 2-8 hours before planting to start the growing process. Plant each seed into dirt 2.5 centimetres deep and 15 to 30 centimetres apart. Plant them after the danger of frost has passed or start indoors three weeks before your last frost date. Keep the soil wet, but not too wet, until the seeds begin to grow.
Sunflower plants can be moved outdoors when the danger of frost has passed in your area. Choose a place outside that will provide the plants with at least 6- 8 hours of direct sunlight each day.
As the plants grow, they will develop long roots that work their way deep into the ground. So, before planting, it is important to loosen the soil. Dig at least one third of a metre down and remove any rocks.
Mixa large amount of compost (堆肥) into the soil where the plant will grow. Compost provides important, lasting nutrients that will help the plants all season long. The sunflowers may not need additional nutrients if they are planted with compost. If compost is not added during the planting process, provide nutrients through a slow release, all-purpose fertilizer (肥料) one or two times during the growing season.
1. What can be known about the sunflower in Paragraph 1?A.It originated in South America. | B.It was initially used to make oil. |
C.It has a history of 3,000 years or so. | D.It was taken to Europe by British explorers. |
A.Keep the seeds in water for 10 hours. |
B.Plant seeds 2.5 centimetres apart. |
C.Never put new plants in direct sunlight each day. |
D.Plant seeds indoors 21 days before your last frost date. |
A.It is friendly to roots’ growth. | B.It helps to hold water in the soil. |
C.It guarantees adequate supplies of air. | D.It is more efficient in keeping temperature. |
A.How to select sunflowers. | B.How to grow sunflowers. |
C.When to fertilize sunflowers. | D.When to move sunflowers. |
2 . In south Africa’s Limpopo province, a baobab tree (猴面包树) once grew so large and stood so strong that its human neighbors decided to build a pub inside the living tree’s thousand-year-old hollow trunk(树干). For 20 years, “The Big Baobab Pub” attracted tourists all over the world. But in August 2016, one of “the walls” broke. Eight months later, another huge piece broke, too. Now, five of the giant stems have collapsed and died, leaving only half of the tree standing.
Though it could sound like a result of human visitation, it's part of an alarming trend: many of the oldest, largest baobab trees in Africa have died within the last 12 years.
Stephan Woodbourne, an African scientist, said: “Of the oldest trees that we’ve looked at in Southern Africa, the three trees that are older than 2,000 years have all died in the past 10 years. Of the 11 trees that are 1,000 to 2,000 years old, six of them have died.”
A report published in the journal Nature Plants claims scores of the ancient baobab trees, some of which are up to 3,000 years old, are now dying because of rising global temperatures.
Researchers believe it is impossible that such a high number of old baobab trees die in such a short time due to natural causes. They think it may be associated with huge change of climate conditions that affect southern Africa in particular.
1. What has happened to The Big Baobab Pub?A.The pub has largely been destroyed. |
B.More tourists from the world visit it. |
C.The pub has a long history of 2,000 years. |
D.The Baobab Tree grows larger and stronger. |
A.all the oldest baobab trees have been dead |
B.the oldest baobab trees will die out soon |
C.ancient baobab trees are in the face of danger |
D.Human’s visits lead to ancient baobab trees’ deaths |
A.Many pubs’ foundation. | B.Global climate changes. |
C.Human visitation. | D.Natural causes. |
A.Research on Baobab Tree. | B.Facts about Baobab Tree. |
C.Baobab Tree in Africa. | D.Tree of Life is Dying. |