Nearly all trees have seeds that fall to the earth, take root, and eventually( ).
A.generate new seeds B.new seeds generated C.generates new seeds D.new seeds are generated
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1.Which of the following is "an illusion"?
2.Many researchers are currently trying to ______.
3.The cutist prejudice probably refers to the fact that ______.
'>For a nation of pet lovers, Britain conducts a surprising number of experiments on animals some 3 m a year. America appears to use fewer animals—just 1.1 m a year, according to official statistics—but that is an illusion. Unlike Britain's government, America's does not think rats and mice worth counting. Japan and China have even less comprehensive data than America, and animals used in research in those two countries are not protected to the same extent that they are in the West. Even so, academic centers supporting alternatives to animal testing have emerged in both places in recent years. In July China issued its first set of guidelines governing the use of animals in research.In an ideal world, there would be no animal testing. It is expensive and can be of dubious scientific value, since different species often react differently to the same procedure. That is why many researchers are working on ways of reducing the number of animal experiments needed and of making those that still happen more effective. However, the transition is proving easier for some types of experiment than for others, as a group of researchers in the field discussed at the sixth World Congress on Alternatives and Animal Use in the Life Sciences, held last week in Tokyo.The most important message from the congress was that things are going in the right direction. The number of animals used in experiments has fallen by half in the past 30 years, at least in those countries that record such things. There has also been a shift in the sort of animal used. Most of those employed today are rodents rather than dogs, cats, rabbits and monkeys. (That public opinion generally welcomes this is, however, a good example of "cutist" pre
"What courses are you going to do next semester?""I don't know. But it's about time ______ on something."
A.I'd decide B.I decided C.I decide D.I'm deciding
Kepler reconciled astronomy with physics, and substituted for fictitious clockwork a universe of material bodies not unlike the earth, freely floating and turning in space, moved by forces（ ）.
A.acted on them B.being acted on it C.acting on them D.having acted on it
There are too many complaints about society having to move too fast to keep up with the machine.
A.that have to B.have to C.having to D.has to
Being born in the summer could give you a sunny disposition for life. And a winter birthday might cast a permanent shadow______your happiness, scientists believe.
A.through B.cross C.beneath D.over