Campus Crime We often think of agriculture as planting seeds and harvesting crops. But many crops do not come from seeds. Ma

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问题                             Campus Crime
    We often think of agriculture as planting seeds and harvesting crops. But many crops do not come from seeds. Many kinds of trees and plants are grown from【C1】______cut from existing trees and plants. This is called grafting(嫁接).
    Farmers cut branches or young growths, called【C2】______, from one plant and place them on a related kind of plant. The branch or bud that is grafted is called a scion(接穗). The plant that【C3】______the graft is called the root stock. Over time, the【C4】______from the two plants grow together. The grafted plant begins to【C5】______the leaves and fruit of the scion, not the root stock.
    A graft can be cut in several ways. A cleft graft(割接,劈接), for example, requires a scion with several buds on it. The bottom of the scion is cut in the【C6】______of the letter V. A place is cut in the root stock to accept the scion. The scion is then【C7】______placed into the cut on the root stock. Growth medium is put on the【C8】______to keep it wet and help the growth.
    Grafting can join scions with【C9】_______ qualities to root stock that is strong and resists disease and insects. Some common fruit trees such as sweet cherries have to be grafted.
    In an age of high-technology agriculture, grafting is a low-technology method that remains【C10】______important.
A)blossoms F)extremely K)grow
B)pieces G)buds L)desirable
C)composes H)agreeable M)produce
D)parts I)accepts N)shape
E)securely J)relatively O)joint
【C10】

选项

答案F

解析
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