Chimney swift (烟囱雨燕) numbers have fallen by more than 70 percent since the 1960s, scientists believe, and by more than one-third over the past 16 years. That large drop have made the International Union for the Conversation of Nature regard chimney swifts as“vulnerable(脆弱的)”. That is the last step before they are considered “endangered”.

Chimney swift numbers are becoming smaller as the shape and design of the nation’s buildings change. People are tearing down old factory buildings and schools. Many of these buildings have chimneys. Today, most American homes do not have chimneys. And many homeowners who do have chimneys cover up the top to keep out.

People across the United States are putting up tall, narrow buildings to help chimney swifts. They hope they will use these buildings as nesting areas and resting places.

Bird lovers, Georgean and Paul Kyle, are often praised for starting the present interest in building towers. “It does give us hope that if we put them up, they will use them,” the Kyles said. They have put up more than 100 towers in Central Texas. Eighty percent of those buildings before the birds’ March arrival get nests in their first year. Hundreds of migrating swifts make use of the towers.

But the link between the drop in chimney swift numbers and chimney loss is not clear. The flying insects that swifts eat also appear to be dropping.

Professor Rubega thinks the cause of the birds’ drop could be in South America. “Chimney swifts are basically a South American bird that stays in North America for four months, ” she said. Rubega said a big problem is that scientists have only a few reports of small numbers of chimney swifts in the upper Amazon Basin. So, they do not really know where the little birds spend the winter, let alone what may be happening to them there.

I am one of the many city people who are always saying that given the choice we would prefer to live in the country away from the dirt and noise of a large city. I have managed to convince myself that if it weren’t for my job I would immediately head out for the open spaces and go back to nature in some sleepy village buried in the country. But how realistic (现实的) is the dream?

Cities can be frightening places. The majority of the population live in huge tower blocks, noisy, dirty and unfriendly. The sense of belonging to a group tends to disappear when you live fifteen floors up. Strangely enough, nowadays people on the same floor don’t even say hello to each other.

Country life, on the other hand, differs in that a sense of group generally unites the people of small villages together. People have the advantage of knowing that there is always someone to turn to when they need help. But it is also true that you are cut off from the exciting and important events that take place in cities. Shopping becomes a major problem, and for anything slightly out of the ordinary you have to go on a trip to the nearest large town. The city people are often worried by a sense of unbearable stillness and quiet.

What, then, is the answer? The country has the advantage of peace and quiet, but suffers from the disadvantage of being cut off. The city raises a feeling of loneliness, and constant noise beats the senses. But you are at the centre of things, and that life doesn’t come to an end at half-past nine at night. Some people have found or rather bought a solution between the two: they have expressed their preference for the “quiet life” by leaving the cities and moving to villages within commuting (通勤) distance of large cities.

What then of my dream? I’m eager for the idea, but you see there’s my cat, Toby. I’m not at all sure that he would take to all that fresh air and exercise in the long grass. I mean, can you see him mixing with all those energetic males down the farm? No, he would rather have the electric fire any evening.

If you plan to learn a foreign language, you might think it’s going to be really challenging. You’ve probably heard a lot of talks about how it’s easier to learn languages as a young child, and that learning as an adult can be difficult. You might even know friends or family members who have tried to learn a foreign tongue and failed. That’s because they are surrounded by the failure. We’re here to cheer you up with some good news and inspire you to get started.

The amazing adult brain: whether you can learn languages at any age? Scientists are always learning about the human brain. Decades ago, experts believed that the brain developed during childhood and then retained that way for life. However, modern studies have shown us that the brain has the ability to continually form new neural (神经的) connections throughout adulthood. A 2010 Swedish study tested two groups of people, one in the range of age 21 through 30 and another between 65 and 80. Remarkably, they found no significant differences in Neuroplasticity (神经可塑性). In other words, this suggests that it’s possible for you to learn new things at any age.

Besides being possible to learn languages, research also suggests that it improves the adult brain in general. In a 2012 Chinese study, experts looked at a group of adults who were learning Mandarin (普通话) over a nine-month period. They found that these adults showed improved integrity in their white matter, the part of the brain that allows neural cells to communicate. The better your neural cells communicate, the easier it will be for you to learn new things.

Why may adults have an easier time learning? Children might be blessed with a naturally high degree of neuroplasticity, but that doesn’t mean learning is necessarily easier for them. In fact, adult brains have a number of great qualities that might actually make learning easier, especially if you take advantage of free language learning apps like Mondly.