单项选择题

A:(),Polly?
B:I’d like a glass of wine,thank you.

A.Do you want
B.What would you like
C.What you like


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1.单项选择题I’ve got a lot of photos of my traveling.Would you ()them.

A.like to see
B.like seeing
C.like see

2.单项选择题

John:Paul,this is Mr Smith,my landlord.
Paul:I’m pleased to meet you.
Mr Smith:().

A.good morning,Paul.
B.very pleased to meet you,too.
C.im fine,too.

4.单项选择题He () himself a great deal of trouble if he had taken the advice of his lawyer last year.

A.would have saved
B.would save
C.had saved
D.would be saved

5.单项选择题Wed better wait till December Bill () his exam by then,so hell be able to enjoy himself.

A.will have had
B.has had
C.is going to have
D.will have

9.If our solar system has a Hell. it&39;s Venus. The air is choked with foul and corrosive sulfur. heaved from ancient volcanoes and feeding acid clouds above. Although the second planet is a step farther from the sunthan Mercury, a runaway greenhouse effect makes it hotter indeed. It&39;s the hottest of the nine plants, a toasty 900 degrees Fahrenheit of baking rocky flats from equator to poles. All this under a crushing atmospheric pressure 90 times that of where you&39;re sitting now. From the earthly perspective, a dead end. It must be lifeless.
"Venus has nothing," is the blunt word from planetologist Kevin Zahnle of NASA Ames Research Center in California&39;s Silicon Valley. "We&39;ve written it off. "
Yet a small group of advanced life-forms on Earth begs to differ. and theorizes that bizarre microbial ecosystems might have once populated Venus and. in fact. may be there still. Members of this loose band of researchers suggest that their colleagues have water too much on the brain, and are, in a sense, H2O chauvinists(盲目的爱国者).
"Astrobiologists are neglecting Venus due more io narrow thinking than actual knowledge of the environment,or environments. where life can thrive." says Dirk Schulze-Makuch, a geobiologist at the University of Texas at El Paso who recently co-authored a Venus-boosting paper in Astrobiology wich colleague Louis Irwin.
The bias against life on Venus is partly rooted in our own biology. Human experience instructs that liquidwater, preferably lot of it. is essential for life. In search for extraterrestrial life, we obsess over small rivers in Mars&39; surface apparently carved by ancient gushes of water. and delight in hints of permafrost (永久冻结带) just underneath its surface. (By comparison. Venus isn&39;t even that interesting to look at:A boring cue ball (台球的白色母球) for backyard astronomers, its clouds reflects 75% of visible light.) Attention and then funding follow the water: Three more landers will depart for Mars this spring. and serious plans for sample-return missions hover in the midterm future.
"If you have limited resources, you base exploration on what you know." says Arizona State University planetary geologist Ronal Greeley. It&39;s like losing your keys on the way home al night: The first place you look is under the streetlights not because they&39;re more likely to be there. but because if they are. you’llspot them. For astrobiologists. the streetlights are the spectral (光谱的) lines for water. and they&39;ve spotted that potential on Mars, Jupiter&39;s moon Europa. even Neptune&39;s moon Triton. Not on the baking rocky flats of Venus.
测试题
Venus is the hottest of all the nine planets in the solar system because_____________.

A.it
J.many
K.it
L.greenhouse

10.If you go down to the woods today, you may meet high-tech trees genetically modified to speed their growthor improve the quality of their wood. Genetically-engineered food crops have become increasingly common, albeit controversial. over the past ten years. But genetic engineering of trees has lagged behind.
Part of the reason is technical. Understanding. and then altering, the genes of a big pine tree are more complex than creating a better tomato. While tomatoes sprout happily, and rapidly, in the laboratory, growing a whole tree from a single, genetically altered cell in a test tube is a tricky process that takes years, not months. Moreover. little is known about tree genes. Some trees, such as pine trees. have a lot of DNA-roughly ten times as much as human. And, whereas the Human Genome Project is more than half-way throughits task of isolating and sequencing the estimated 100,00 genes in human cells. similar efforts to analyzetree genes are still just saplings (幼苗).
Given the large number of tree genes and the little that is known about them, tree engineers are starting with a search for genetic "markers". The first step is to isolate DNA from trees with desirable propertiessuch as insect resistance. The next step is to find stretches of DNA that show the presence of a particular gene. Then, when you mate two trees with different desirable properties, it is simple to check which offspring contain them all by looking for the genetic markers. Henry Amerson, at North Carolina State University, is using genetic markers to breed fungal resistance into southern pines. Billions of these are grown across America for pulp and paper, and outbreaks of disease are expensive. But not all individual trees are susceptible. Dr. Amerson’s group has found markers that distinguish fungus-resistant stock from disease-prone trees.Using traditional breeding techniques, they are introducing the resistance genes into pines on test sites in America.
Using generic markers speeds up old-fashioned breeding methods becauseyou no longer have to wait for the tree to grow up to see if it has the desiredtraits. But it is more a sophisticated form. of selective breeding. Now. however.interest in genetic tinkering (基因修补) is also gaining ground. To this end, Dr.Amerson and his colleagues are taking part in the Pine Gene Discovery Project. an initiative to identify and sequence the 50,000-odd genes in the pine tree&39;s genome. Knowing which gene does what should make it easier to know what to alter.
测试题
Compared with genetic engineering of food crops, genetic engineering of trees____________________.

A.began
I.has
J.is
K.was

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Choose the most appropriate words to complete the summary of Unit 3 Passage A(每词只选一次,只需填字母)The passage is speaking strongly against the patent system--based upon the (1)______that “patent-lawyers are s of obfuscation” and that patents are being used both by established (2)______and patent trolls to stifle further innovation. The system has created a parasitic (3)_______ of trolls and defensive patent-holders, who aim to block innovation, or at least to stand in its way (4)______ they can grab a share of the spoils. An early study found that newcomers to the semiconductor business had to buy licenses from incumbents for as much as $200m. Patents should spur (5)_______ of innovation; instead, they are used to lock in incumbents' advantages. The patent system is expensive. A decade-old study (6)_______ that in 2005, without the temporary monopoly patents bestow, America might have saved three-quarters of its $210 billion bill for prescription drugs. The expense would be worth it if patents brought innovation and prosperity. The Economist has a longstanding pro-competition anti-patent bent. In the 1800's The Economist proposed full (7)______of the patent system. The paper's stance is no longer opposition, but does come with the interesting statement that “government should force the owners of intellectual property to share.” Their proposals: 1) Patent Use Requirement--the patent should only be (8)______ if the patentee uses it in the marketplace. 2) Patent (9)______--patents should be easier to challenge without going to court and the burden of proof should be lower. 3) The standard for non-obviousness should be raised so that patents are only granted to those “who work hard on big, fresh ideas, rather than those who file the paperwork on a tiddler.” 4) Patent term should be reduced--(10)______ in fast-moving technology areas.

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