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Want to help butterflies? A new study suggests turning off the lights.

Light pollution at night can disturb its abilities to recognize directions，researchers have found.Artificial light can disrupt their circadian(昼夜节律的) rhythms and affect their sense of directions.That can make the butterflies disoriented when they try to fly the next day.

"Darkness is important to butterflies since the internal circadian clock of butterflies functions normally when they are exposed to natural day-night lighting cycles，" study author Patrick Guerra，an assistant professor at the University of Cincinnati，tells Treehugger.

Monarch butterflies migrate(迁徙) by the millions each year，making the trip from northern areas of the continent to California and Mexico and back.Because most butterflies only live for a few weeks to a few months，it takes several generations of butterflies to complete the migration.But too much light at the wrong time can urge the butterflies to take off when they should be resting instead for their voyage.

"As monarch butterflies are a threatened species with their population numbers in decline，we wanted to see what types of environmental stress might be linked to their decline，" Guerra says.

For their study，researchers conducted lab studies where they reproduced the effects of artificial light pollution with butterflies using a flight simulator(模拟器). 

They first tested if monarchs treated a single，artificial light source as if it were the actual sun during the day.Once they established what they did，they then tested how the monarchs would behave when exposed to this same artificial light source during their night.

Butterflies stayed quiet and unmoving when they were first placed in the flight simulator in the dark.But as soon as scientists turned on the light，they started flying.The light made them believe that night was day and this can cause them to fly longer at night or start flying too early.

"These findings demonstrate how urbanization can negatively affect important biological phenomena，and therefore allow us to understand how human activity impacts the rest of nature，" Guerra says.

Museums in Baltimore

The Walters Art Museum

The Walters Art Museum contains 36,000 objects from around the world.Walking through the museum's historic buildings，visitors encounter a stunning panorama of thousands of years of art，from romantic 17th-century images of French gardens to fascinating Ethiopian icons，ancient Roman sarcophagi(石棺)，and peaceful images of the Buddha.

Tickets：$9.5.Free for children aged 7 and under.

Baltimore Museum of Industry

The Baltimore Museum of Industry celebrates the innovators，entrepreneurs and workers who promoted this port city into the industrial age.From garment making to airplane manufacturing，visitors to the museum will discover how their pioneering spirit built the region's manufacturing might.Located in an 1860s oyster cannery on a five-acre waterfront campus，the BMI offers dynamic exhibitions and hands-on activities for guests of all ages.

Tickets：$15.Half price for children.

Baltimore Museum of Art

The Baltimore Museum of Art is home to an internationally renowned collection of 19th-century，modern，and contemporary art.It has 90,000 works of art—including the largest holding of works by Henri Matisse in the world.The BMA is now throughout the multi-year project so that visitors can enjoy its outstanding selection of European and American painting and sculpture from the 17th through 20th centuries.

Tickets：$10.Ten percent off if booked on the official website.

American Visionary Art Museum

The American Visionary Art Museum is the nation's museum for self-taught，creative skills.Three historic buildings house wonders created by farmers，housewives，mechanics，the disabled，as well as the occasional neurosurgeon.From carved roots to embroidered rags，tattoos to toothpicks，"the visionary" transforms dreams，loss，hopes，and ideals into powerful works of art.

Tickets：$9.5.Free for children aged 6 and under and museum members.

Technology has changed our lives and reshapes the way we live.Some of us love it and some of us are frustrated(懊恼的) with it.This is clear as most of us are guilty of being addicted to the Internet and social media. Technology has created a whole new world and brought endless opportunities.

The invention of airplanes，ships and spacecraft always allows people to visit other countries and even other planets.As long as we follow the laws of immigration，we can go to any country we like.

In addition，technology is also used by a large number of teachers to improve their teaching.It can make the lessons more interactive and interesting for students.E-learning is possible with the use of the Internet connection and computers.People wishing to study for a degree can do so at their comfortable homes. Teachers can post notes and videos on the Internet and students can study and learn whenever they are ready.

You don't have to walk around with a large sum of cash any more because you can make purchases and payments electronically.Online banking is secure and convenient for online shopping.You don't have to worry that your cash might be stolen by someone.

However，we have to say that technology can be a double-edged sword.Nowadays，instead of paying attention to the conversation we are having face to face，we just take the phone.We are distracted by smartphones and technology in general.But we can't blame technology.We should not blame ourselves，either. Indeed，technology is addictive，but our focus shouldn't be on phones or computers，but on people and face-to-face conversations.

A. This gives students flexibility.

B. What we need to do is to find some balance.

C. This makes it easy for students to make progress.

D. Nevertheless，we have seen some benefits of technology.

E. When it comes to shopping，technology is also of great help.

F. Besides，we have suffered a lot from modern communication.

G. And of course，travelling can make people's lives more colorful.

Human is struggling to contain two major crises：Skyrocketing global temperatures and deep-diving biodiversity(生物多样性). But people tend to solve each problem on its own, for instance by using green energies and carbon-eating machines, while surrounding ecosystems to preserve them. But a new report argues that treating each crisis in isolation(孤立地) means missing out on solutions that resolve both. Human can't solve one without also solving the other.

So what might these solutions look like？Say, for instance, you turn a heavily logged forest into a national park. As the trees grow back, they would provide habitat for the return of animals. Letting a forest come back naturally, rather than planting trees of a single species to balance up some corporations' carbon emissions(排放), makes it recover faster. This is known as a nature-based solution, a campaign that both absorbs carbon and provides an extra ecological or economic benefit.

Stopping human's attacks on ecosystems can also help fight climate change, the study's authors write. Even cities can get in on the action, the report notes. Urban areas turn into "heat islands"because they absorb the sun's energy during the day and slowly release it at night. They are therefore much hotter than surrounding rural areas. Planting more trees cools cities and provides habitats for birds and shade for humans, which will be even more critical as global temperatures rise.

The big threat, the authors stress, is that nature-based solutions alone can't stop climate change. As temperatures climb and droughts get more severe, it'll be harder for forests, wetlands, and mangroves to survive, even with our help. First and foremost, human has to dramatically reduce its greenhouse gas emissions. "Nature is not going to save us, "the authors say. "We can only use nature to support efforts. "

"Still, governments and corporations are becoming more conscious of the importance of maintaining biodiversity while also fighting climate change, "says Beymer-Farris, from the University of Kentucky. "As a professor who has been working on this for 20 years, I see a lot of hope, because I see a lot of changes on the horizon. "

Have you ever heard someone say，"Breakfast is the most important meal of the day"，or give you advice about why it's vital to start the day with a healthy breakfast? It seems that this meal，for many of us，is necessary for our day to start well，but is it really that important?

The word "breakfast"comes from "breaking the fast(禁食)"—the idea of ending the period in which we don't eat during the night.The regeneration process that takes place while we sleep consumes some of our natural food reserves.Breakfast gives us an opportunity to replenish those reduced stores of things like protein and calcium.So，in that way，a healthy breakfast makes sense.

There are also many often-quoted studies which seem to connect a state of being overweight with not eating breakfast.In fact，it leads many health experts to advise a healthy breakfast to not only control but also lose weight.In a US study，50，000 people were monitored over seven years，and those who ate a healthy breakfast were found to have a lower BMI(体重指数)，which seems to suggest that breakfast may indeed help people maintain a healthy weight.

But it might not be as simple as that.Alexandra Johnstone，professor of appetite research at the University of Aberdeen，suggests those who do not have breakfast might be less aware of healthy diets and nutrition，and people who eat breakfast might have a healthier lifestyle overall—exercising and not smoking，for example.And he also points out that with the rise in popularity of intermittent(间歇的) fasting to lose weight，there may also be some benefits to not eating breakfast，like improving blood sugar control and lowering blood pressure.

So，while breakfast has its benefits，it might not be the most important meal.It seems that a healthy lifestyle with a balanced diet might be more important for many of us than just one single meal.

Candles were burning bright, exciting my two-year-old son, Jack, who moved forward to blow them out.

Jack's third birthday was still a few months away but ever since his dad Gary's big day earlier that year, my son hadn't stopped talking about celebrating his own. His older brothers Oliver, 6, and Josh, 10, were happy to sing the birthday song with him.

But, over time, I grew concerned that Jack wasn't well. My lovely boy was now a shadow of his former self. How could I ignore it, though doctors weren't too concerned?

One day I was at work and shared my fears with a colleague. She comforted me and said it was safe to be careful. When I returned home later, I packed a bag and prepared to take Jack to hospital.

At the hospital, I just couldn't shake the feeling that bad news was coming. My suspicions(怀疑) were confirmed. We were told he had a very rare form of cancer.

Jack was going downhill rapidly. Gary and I took it in turns to stay with him in the hospital. "Your birthday's coming up, "I told Jack each day, hoping he could remember the times we had sung him happy birthday before.

"Jack's only option is a stem cell transplant(干细胞移植), and a brother or a sister might be the best chance you have, "a doctor told us. "He can have my head if he needs it！"Josh cried. Oliver wasn't as enthusiastic as his older brother, but it was a huge relief when he was confirmed as a match.

Doctors were cautious about saying Oliver might save Jack's life in case it didn't work as planned. To their relief, the result was comforting. They were moved by Oliver's bravery.

Oliver, now seven, really did save his little brother and they're now closer than ever. "I didn't want to do it at the very beginning but at the end I kind of regretted feeling like that because now I know how important it was, "he said. 

Only by putting  into use can you master Chinese as quickly as possible. 

When we arrived at the farm,  and fruit trees in the farm. 

, Father said in a warm voice, "Darling, it is love that counts. "

Besides, , we are busy making final preparations. 

Please forgive me for my not accompanying you to the bookstore because there are  today.