【推荐1】Recently, a small group of bird-watchers spent three weeks around Mount Vernon. They were busy _______ wild birds on Mount Vernon’s wetlands, south of Washington, D.C. They began in the middle of December and _______ until the beginning of January.

The bird-watchers were among 70,000 volunteers who collected _______ for the National Audubon Society. Its first “Christmas Bird Count” took place 115 years ago in 1900 _______ a man named Frank Chapman suggested a new Christmas _______ that people count birds _______ shooting them around the holiday.

Harry Glasgow _______ the Christmas Bird Count 10 years ago. This year, he was one of the volunteer bird-watchers at Mount Vernon. “I think it’s great _______ of a lot of talent around the nation to keep track of birds. Birds are one of the _______ signs of the health of the ecology.”

Last year, the bird count ________ over 66 million birds of 2,403 different species. Over half the birds in North America — 314 out of 588 species — are seriously ________ by climate change. The impacts cut across all birds, all sizes, all kinds, and all places.

Information from the bird counts has shown that birds are ________ farther north during the winter months because of ________ weather. Bird-watcher Jaime Reidy has noted the difference close to Washington, in the state of Virginia. “You get to see them at ________ times of the year, a little earlier, ________ a little later.”

Gary Langham says other conditions are affecting bird ________. “You can imagine the number of the birds that live along the beach or along the rocky shoreline as sea level is ________ because of global warming around the world.”

David Yarnold says, “Christmas Bird Count data are becoming important not only in ________ current climate change, but in judging the future ________ of climate change on North American bird populations. If we know what to expect, we can start taking ________ now to do something about it.”

【推荐3】If you like to take a walk in the woods in the United States or you prefer to decorate a tree at Christmas, you should know that climate change is making both of those activities a lot more ___________.

Looking at two ___________ and economically important species - the Douglas fir and the Ponderosa pine -scientists found that fires and drought _____________ by climate change make new growth difficult, especially in low-elevation forests, according to a study published Monday in the Proceedings of the National Academy of Sciences.

Some forests in four regions in California, Colorado, the Northern Rockies and the southwestern part of the United States have crossed ''a(n) ___________ climate tipping(转折)point for post-fire tree generation, '' the study says.

Climate conditions over the past 20 years have _____________ changes that would have taken decades or even centuries to ___________ across broad regions of the country. This is leading to the sudden _____________ of trees and making these lands increasingly unsuitable for tree regeneration.

''Climate changes is _____________ our forests now, not just in some distant future. Maybe in areas where there are really _____________ seed sources, there could be some trees, but it is becoming really hard to get these trees back due to climate change, '' said study co-author Kim Davis.

The problem probably won't get any better, as climate change is making intense wildfires much more ______________. Western foresters say there used to be a fire season. But devastating and ____________ fires have become a reality all year long. In 2018, fire cost California more than $9.05 billion, according to the USA insurance commissioner, the deadliest and most destructive wildfires season in the ________________ history.

A higher number of fires and low seed availability means a high probability that these trees in these regions won't come back, Davis said. This study ______________ on the driest and hottest areas of the Western forests, but researchers will next try to focus on how much will be impacted.

____________, there are some things people can do to ease some of this problem. Forest management plans that reduce high-severity burns can help. Increasingly, forest managers are considering allowing some fires to burn under more moderate conditions, Davis said, Forest ______________can also replant trees after fire, at least in the areas where climate conditions will allow.

【推荐1】Scientists in Norway have more good news for coffee drinkers. Researchers have already found evidence that the drink — or the beans can help with weight loss, _______one's risk of developing some diseases, _______ muscle growth, protect against certain types of cancers and can even reduce one's risk of _______ death. Now comes word that a cup of coffee reduces physical pain.

The surprising finding is based on a study _______ 48 volunteers who agreed to spend 90 minutes performing fake computer tasks meant to mimic office work. The tasks were known to _______pain in the shoulders, neck, forearms and wrists, and the researchers wanted to _________ how people with pain and those who were pain-free tolerated the pain of such tasks. As a matter of convenience, the scientists allowed people to drink coffee before taking the test "to avoid _______effects of caffeine deprivation, e.g. decreased vigor and alertness, sleepiness, and fatigue," they reported.

But when it came time to analyze the data, the researchers from Norway's National Institute of Occupational Health and Oslo University Hospital noticed that the 19 people who drank coffee reported a lower _______ of pain than the 29 people who didn't. In the shoulders and neck, _______, the average pain intensity was rated 41 (on a 100-point scale) among the coffee drinkers and 55 for non-coffee drinkers. Similar gaps were found for all pain sites measured, and coffee's apparent pain-reduction effect ________.

However, the authors of the study, which was published this week in the journal BMC Research Notes, cautioned that since the study wasn't designed to test coffee's influence on pain, the results came with many ________. For starters, the researchers don't know how much coffee the coffee drinkers consumed before taking the computer tests. ________they doubt whether the coffee drinkers and non-coffee drinkers were ________in all respects except for their coffee consumption. Problems like these tend to ________ the importance of the findings. But those doubts are ________ to trouble the coffee drinkers looking for any reason not to cut back on their daily caffeine habit.

【推荐2】When we think about lives filled with meaning, we often focus on people whose grand contributions benefited humanity. Abraham Lincoln, Martin Luther King, Jr., and Nelson Mandela surely felt they had a worthwhile life. But how about us ordinary people, burying ourselves in a(n) ________ existence?

Many scholars ________ a subjectively meaningful life to three factors: the feeling that one’s life makes sense (coherence), the possession of clear and satisfying long-term goals (purpose) and the belief that one’s life matters in the overall scheme of things (________ mattering).

But we believe there is another element to consider. Think about the first butterfly you stop to admire after a long winter. Sometimes existence delivers us small moments of beauty. When people are ________ to appreciating such experiences, these moments may enhance how they view their life. We call this element experiential appreciation, which represents the detection of and ________ for life’s inherent beauty.

To better understand this form of appreciation, we conducted a series of experiments in which we gave people specific tasks and asked them to report how strongly they ________ statements linked to the factors of meaningful life. In one case, we found that participants who watched an awesome video, such as the BBC documentary Planet Earth, reported having a greater sense of experiential appreciation and meaning in life, compared with participants watching more ________ videos, such as an instructional woodworking video. ________, participants who wrote about a recent experience for which they were ________ had a greater sense of meaning when compared with those who simply wrote about a common place they had ________ last week.

The results confirmed our original theory: people are born with the ability to appreciate beauty, and appreciating small things can make life feel more meaningful. But ________ that insight can be difficult. Our modern, fast-paced, ________ lifestyles fill the day with targets. We attempt to ________ output both at work and at leisure. This focus on future outcomes makes it all too easy to miss what is happening right now. Yet life happens in the present moment. We should slow down, let life surprise us and ________ the significance in the everyday. As former Indian prime minister Jawaharlal Nehru wrote in 1950, “We live in a wonderful world… There are countless adventures that we can have if we ________ them with our eyes open.”

【推荐3】The scent of coffee appears to enhance performance in math

Drinking coffee has benefits. ______ the physical improvement, coffee may reduce our risk of heart disease. Coffee may even help us live longer. Now, research also reveals that the scent（气味）of coffee may help people perform better on the analytical portion of the Graduate Management Aptitude Test, or GMAT, a computer adaptive test ______ by many business schools.

The work, led by famous professor Adriana Madzharov, not only ______ the hidden force of scent and the cognitive（认知）improvement it may provide on analytical tasks, but also expectation that students will perform better on those tasks. Madzharov, with his colleagues, recently published their findings.

“It’s not just that the coffee-like scent helped people perform better on analytical tasks, which was already ______,” says Madzharov. “But they also thought they would do better, and we demonstraded that this expectation was at least partly ______ their improved performance.” ________, smelling a coffee - like scent, which has no caffeine in it, has an effect similar to that of drinking coffee, suggesting a placebo（安慰剂）effect of coffee scent.

Madzharov’s team tested 100 undergraduate business students, divided into two groups, with GMAT algebra questions. One group took the test in the ______ of a coffee - like scent, while a control group took the same test - but in an unscented room. They found that the group in the coffee-smelling room scored significantly higher on the test.

Madzharov’s team wanted to know more. Could the first group’s performance in quick thinking be explained, in part, by an expectation that a coffee scent would increase ______ and consequently improve performance?

The team designed a follow-up survey, conducted among more than 200 new participants, quizzing them on ______ about various scents and their effects on human performance. Participants believed that they would feel more alert and energetic in the presence of a coffee scent, in contrast with a flower scent or no scent; and that ______ to coffee scent would increase their performance on mental tasks. The results suggest that ______ about performance can be explained by beliefs that coffee scent alone makes people more alert and energetic.

Madzharov is now looking to explore whether coffee-like scents can have a(n) ______ placebo effect on other types of performance, such as verbal reasoning. She also says that the finding - that coffee - like scent acts as a placebo for analytical reasoning performance - has many practical ______, including several for business.

“Sense of smelling is one of our most powerful senses,” says Madzharov. “Employers, architects, building developers, retail space managers and others, can use scents to help ______ employees’ or occupants’ experience with their environment. It’s an area of great interest and ______.”

【推荐2】People live in the present. They plan for the future. History, _________, is the study of the past. Given all the demands and pressures that come from living in the present and _________ what is yet to come, why bother with what has been? Given all the available branches of knowledge, why insist — as most educational systems do — on history? And why encourage many students to study even more history than they are _________ to?

Any subject of study needs to be _________: supporters must explain why it is worth _________. Like most widely accepted subjects, history attracts people who simply _________ the information and modes of thought involved. But for people who are less interested in the subject and more _________ about why they should bother with it, a clearer explanation of its purpose is required.

_________do not perform heart transplants, improve highway design, or arrest criminals. In a society that quite correctly expects education to serve useful purposes, history’s functions can seem more _________ to determine than those of engineering or medicine. History is in fact very useful, actually ____________, but the products of historical study are often less ____________ and immediate than those of other subjects.  

History helps us understand people, societies and how they____________. For example, how can we ____________ past wars (and future threats) without using historical materials? Unfortunately, major aspects of a society’s operation cannot be set up as precise experiments. ____________, history must serve, however imperfectly, as our laboratory, helping us understand who we are and why we do what we do. This, fundamentally, is why we cannot ____________ history.