Dinosaurs died out suddenly about 65 million years ago. Some scientists think it came after an unexpected incident when a huge rock from space hit the earth and put too much dust into the air. Others think the earth got too hot for the dinosaurs to live on any more. Nobody knows for sure why and how dinosaurs disappeared from the earth in such a short time.
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【推荐1】According to the Solar Energy Industry Association, the number of solar panels installed(安装)has grown rapidly in the past decade, and it has to grow even faster to meet climate goals. But all of that growth will take up a lot of space, and though more and more people accept the concept of solar energy, few like large solar panels to be installed near them.
Solar developers want to put up panels as quickly and cheaply as possible, so they haven’t given much thought to what they put under them. Often, they’ll end up filling the area with small stones and using chemicals to control weeds. The result is that many communities, especially in farming regions, see solar farms as destroyers of the soil.
“Solar projects need to be good neighbors,” says Jordan Macknick, the head of the Innovative Site Preparation and Impact Reductions on the Environment(InSPIRE)project. “They need to be protectors of the land and contribute to the agricultural economy.” InSPIRE is investigating practical approaches to “low-impact” solar development, which focuses on establishing and operating solar farms in a way that is kinder to the land. One of the easiest low-impact solar strategies is providing habitat for pollinators(传粉昆虫).
Habitat loss, pesticide use, and climate change have caused dramatic declines in pollinator populations over the past couple of decades, which has damaged the U.S. agricultural economy. Over 28 states have passed laws related to pollinator habitat protection and pesticide use. Conservation organizations put out pollinator-friendliness guidelines for home gardens, businesses, schools, cities—and now there are guidelines for solar farms.
Over the past few years, many solar farm developers have transformed the space under their solar panels into a shelter for various kinds of pollinators, resulting in soil improvement and carbon reduction. “These pollinator-friendly solar farms can have a valuable impact on everything that’s going on in the landscape,” says Macknick.
What is the purpose of the laws mentioned in paragraph 4?
A.To conserve pollinators. |
B.To restrict solar development. |
C.To diversify the economy. |
D.To ensure the supply of energy. |
【推荐2】Early fifth-century philosopher St.Augustine famously wrote that he knew what time was unless someone asked him.Albert Einstein added another wrinkle when he theorized that time varies depending on where you measure it.Today’s state-of-the-art atomic(原子的) clocks have proven Einstein right.Even advanced physics can’t decisively tell us what time is, because the answer depends on the question you’re asking.
Forget about time as an absolute.What if,instead of considering time in terms of astronomy,we related time to ecology?What if we allowed environmental conditions to set the tempo(节奏) of human life?We’re increasingly aware of the fact that we can’t control Earth systems with engineering alone,and realizing that we need to moderate(调节)our actions if we hope to live in balance.What if our definition of time reflected that?
Recently,I conceptualized a new approach to timekeeping that’s connected to circumstances on our planet,conditions that might change as a result of global warming.We’re now building a clock at the Anchorage Museum that reflects the total flow of several major Alaskan rivers,which are sensitive to local and global environmental changes.We’ve programmed it to match an atomic clock if the waterways continue to flow at their present rate.If the rivers run faster in the future on average,the clock will get ahead of standard time.If they run slower,you’ll see the opposite effect.
The clock registers both short-term irregularities and long-term trends in river dynamics.It’s a sort of observatory that reveals how the rivers are behaving from their own temporal frame(时间框架),and allows us to witness those changes on our smartwatches or phones.Anyone who opts to go on Alaska Mean River Time will live in harmony with the planet.Anyone who considers river time in relation to atomic time will encounter a major imbalance and may be motivated to counteract it by consuming less fuel or supporting greener policies.
Even if this method of timekeeping is novel in its particulars,early agricultural societies also connected time to natural phenomena.In pre-Classical Greece,for instance,people“corrected” official calendars by shifting dates forward or backward to reflect the change of season.Temporal connection to the environment was vital to their survival.Likewise,river time and other timekeeping systems we’re developing may encourage environmental awareness.
When St.Augustine admitted his inability to define time, he highlighted one of time ‘s most noticeable qualities:Time becomes meaningful only in a defined context.Any timekeeping system is valid,and each is as praiseworthy as its purpose.
What can we learn from this passage?A.Those who do not go on river time will live an imbalanced life. |
B.New ways of measuring time can help to control Earth systems. |
C.Atomic time will get ahead of river time if the rivers run slower. |
D.Modern technology may help to shape the rivers’ temporal frame. |
A. Based on people’s grammar scores and information about their learning of English, the researchers developed models that predicted how long it takes to become fluent in a language and the best age to start learning.
B. To find the answer, the research team turned to the Internet, to collect data on a person’s current age, language ability and time studying English.
C. The older you get the more difficult it is to learn to speak English like a British. But no one knows exactly at what age it becomes harder, to learn a new language.
D. They concluded that the ability to learn a new language is strongest until the age of 18. This is not to say that we cannot learn a new language if we are over 18, but most of us will not be able to master grammar like a native speaker.
E. They also created a short online grammar quiz that tested noun-verb agreement, pronouns, prepositions, and relative clauses, etc.