下列图形中,是轴对称图形的是( ) A.任意两个点 B.梯形 C.平行四边形 D

题型:选择题

问题:

下列图形中,是轴对称图形的是(  )

A.任意两个点

B.梯形

C.平行四边形

D.任意三角形

考点:轴对称
题型:选择题
阅读文章,把方框中代表句子的字母A、B、C、D、E填到文章中划线部分的相应位置上。
A. If the new species (物种) is too strong or uses too much of the resources (资源) in the habitat.
B. We often talk about how important it is to take good care of ourselves and our planet
C. When farmers cut down trees, tigers can no longer hide and hunt
D. Steve says that we can help by creating more space for animals and plants
E. A species can become endangered for different reasons
                                                          Are we endangered?
     Steve Jones is an environmental expert who tries to keep animals and plants from becoming endangered.
"We are not alone in the world. We human beings could not survive (生存) without all the plants and animals
around us. 1           , but we don't always do as we say," Steve says as he takes us on a tour of Green Park
in Birmingham. Many of the earth's plants and animals have already died out, and several other species are
endangered. If we want to live a better life and have a bright future, we must learn to act in ways that do not
harm other living things.
     If we know more about what causes endangerment, we may be able to take measures (采取措施) before
it is too late. 2           . Animals and plants must have a habitat, or home, which is comfortable and clean,
and where there is enough food and other resources. They are all used to their environment; that is, they have
learnt how to live successfully in their habitat. When the habitat of a species is changed or destroyed, the
animal or plant had to either adapt to the change or find a new home. If this is not possible, the species becomes
endangered. If a new species arrives, the animals and plants of the habitats must change again. 3          , some
of the original (原始的) species may become endangered. A species may also die out if humans or other animals
use too much of a plant or kill too many animals.
     The good news is that there is a lot we can do to help. First of all, we need to learn more about animals,
plants and the environment. Experts tell us that we need to think about what we can do to keep animals and
plants from becoming endangered. 4           :"You can plant a tree or build a birdhouse. It is simple but useful."
Steve also wants us to think about what we do: "Please don't pollute the environment." If we find out more
about what we should do, we can help Steve and others like him keep. animals and plants and ourselves from
becoming endangered.
题型:选择题

We must stress that these payment terms ( )very important to us.

A.be

B.being

C.been

D.are

题型:选择题

诱导免疫耐受的方法是()

A.切除成年动物的胸腺

B.切除成年动物的脾脏

C.注射佐剂

D.注射极大量Ag

E.注射有丝分裂素和Ag

题型:选择题

试述凹凸工艺。

题型:选择题

Think of those fleeting moments when you look out of an aeroplane window and realise that you are flying, higher than a bird. Now think of your laptop, thinner than a brown-paper envelope, or your cellphone in the palm of your hand. Take a moment or two to wonder at those marvels. You are the lucky inheritor of a dream come true.

The second half of the 20th century saw a collection of geniuses, warriors, entrepreneurs and visionaries labour to create a fabulous machine that could function as a typewriter and printing press, studio and theatre, paintbrush and gallery, piano and radio, the mail as well as the mail carrier. (41)

The networked computer is an amazing device, the first media machine that serves as the mode of production, means of distribution, site of reception, and place of praise and critique. The computer is the 21st century’ s culture machine.

But for all the reasons there are to celebrate the computer, we must also tread with caution. (42) I call it a secret war for two reasons. First, most people do not realise that there are p commercial agendas at work to keep them in passive consumption mode. Second, the majority of people who use networked computers to upload are not even aware of the significance of what they are doing.

All animals download, but only a few upload. Beavers build dams and birds make nests. Yet for the most part, the animal kingdom moves through the world downloading. Humans are unique in their capacity to not only make tools but then turn around and use them to create superfluous material goods—paintings, sculpture and architecture—and superfluous experiences—music, literature, religion and philosophy. (43)

For all the possibilities of our new culture machines, most people are still stuck in download mode. Even after the advent of widespread social media, a pyramid of production remains, with a small number of people uploading material, a slightly larger group commenting on or modifying that content, and a huge percentage remaining content to just consume. (44)

Television is a one-way tap flowing into our homes. The hardest task that television asks of anyone is to turn the power off after he has turned it on.

(45)

What counts as meaningful uploading My definition revolves around the concept of"stickiness" — creations and experiences to which others adhere.

[A] Of course, it is precisely these superfluous things that define human culture and ultimately what it is to be human. Downloading and consuming culture requires great skills, but failing to move beyond downloading is to strip oneself of a defining constituent of humanity.

[B] Applications like tumblr.com, which allow users to combine pictures, words and other media in creative ways and then share them, have the potential to add stickiness by amusing, entertaining and enlightening others.

[C] Not only did they develop such a device but by the turn of the millennium they had also managed to embed it in a worldwide system accessed by billions of people every day.

[D] This is because the networked computer has sparked a secret war between downloading and uploading —between passive consumption and active creation -- whose outcome will shape our collective future in ways we can only begin to imagine.

[E] The challenge the computer mounts to television thus bears little similarity to one format being replaced by another in the manner of record players being replaced by CD players.

[F] One reason for the persistence of this pyramid of production is that for the past half-century, much of the world’s media culture has been defined by a single medium—television—and television is defined by downloading.

[G] The networked computer offers the first chance in 50 years to reverse the flow, to encourage thoughtful downloading and, even more importantly, meaningful uploading.

41()

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