1 . Now let us look at how we read. When we read a printed text, our eyes move across a page in short, rough movement. We recognize words usually when our eyes are still when they fixate (凝视). Each time they fixate, we see a group of words. This is known as the recognition span or the visual span. The length of time of which the eyes stop -the duration of the fixation — varies considerably from person to person. It also varies within one person according to his purpose in reading and his familiarity with the text. Furthermore, it can be affected by such factors as lighting and tiredness.

Unfortunately, in the past, many reading improvement courses have concentrated too much on how our eyes move across the printed page. As a result of this misleading emphasis on the purely visual aspects of reading, numerous exercises have been devised to train the eyes to see more words at one fixation. For instance, in some exercises, words are flashed on to a screen for, say, a tenth or a twentieth of a second. One of the exercises has required students to fix their eyes on some central point, taking in the words on either side. Such word patterns are often constructed in the shape of rather steep pyramids so the reader takes in more and more words at each successive fixation. All these exercises are very clever, but it’s one thing to improve a person’s ability to see words and quite another thing to improve his ability to read a text efficiently. Reading requires the ability to understand the relationship between words. Consequently, for these reasons, many experts have now begun to question the usefulness of eye training, especially since any approach which trains a person to read isolated words and phrases would seem unlikely to help him in reading a continuous text.

2 . Brown bears have stopped eating salmon（鲑鱼）in favor of elderberries after being forced to make a choice due to climate change. Warming temperatures mean that the berries are ripening earlier than usual, at exactly the same time as the freshwater streams on Alaska’s Kodiak Island are over flowing with salmon.

The island’s brown bears typically feed first on salmon in early summer, followed by elderberries later in the season, in late August and September.

“What you have is a scrambling of the schedule,” said William Deacy, a biologist at Oregon State University that studied the phenomenon.

“It’s essentially like if breakfast and lunch were served at the same time and then there is nothing to eat until dinner. You have to choose between breakfast and lunch because you can only eat so much at a time.”

The study found that during the unusually warm summer of 2014, the bears, which would traditionally kill up to 75 percent of the salmon, were nowhere to be seen near the streams. Instead, they were in the hills busy munching on berries, which contain less protein and therefore take less energy to break down, causing them to gain weight more quickly.

Biologists warned that changes caused by a warming planet were behind the bears’ unusual behavior and could affect the entire ecosystem.

The researchers found that the forests around the streams suffered because the bears’ fish carcasses（残骸）were no longer there to enrich the soil.

“Bears switched from eating salmon to elderberries, disturbing an ecological link that typically fertilizes the ecosystems and generates high death rates for salmon,” the study said. On average, red elderberries are said to be ripening two and a half days earlier every decade. If the pattern continues, they will regularly overlap（重叠）with the salmon by 2070.

3 . Money with no strings attached. It’s not something you see every day. But at Union Station in Los Angeles last month, a board went up with dollar bills attached to it with pins and a sign that read, “Give What You Can, Take What You Need.”

People quickly caught on. And while many took dollars, many others pinned their own cash to the board. “People of all ages, races, and socio-economic (社会经济的) backgrounds gave and took,” said Tyler Bridges of The Toolbox, which created the project. “We even had a bride in her wedding dress come up to the board and take a few dollars.” Most of the bills on the board were singles, but a few people left fives, tens and even twenties. The video clip (片段) shows one man who had found a $ 20 bill pinning it to the board.

“What I can say for the folks that gave the most, is that they were full of smiles,” Bridges said. “There’s a certain feeling that giving can do for you and that was apparent in those that gave the most.” Most people who took dollars took only a few, but Bridges said a very small number took as much as they could.

While the clip might look like part of a new ad campaign, Bridges said the only goal was to show generosity and sympathy. He added that he hopes people in other cities might try similar projects and post their own videos on the Internet.

“After all, everyone has bad days and good days,” he said. “Some days you need a helping hand and some days you can be the one giving the helping hand.”

5 . More than 60 years and almost 1,200 donations later, Harrison, whose blood contains an antibody (抗体) that has saved the lives of 2.4 million babies from miscarriages (流产), retired as a blood donor on May 11. Harrison’s blood is valuable because he naturally produces Rh-negative blood, which contains Rh-positive antibodies. His blood has been used to create anti-D in Australia since 1967.

“Every bottle of anti-D ever made in Australia has James in it,” Robyn Barlow, the Rh program director told the Sydney Morning Herald. “It’s an amazing thing. He has saved millions of babies. I cry just thinking about it.” Since then, Harrison has donated between 500 and 800 milliliters of blood almost every week. “I’d keep going if they let me,” Harrison told the Herald. His doctors said it was time to stop the donations. They had already extended the age limit for blood donations for him, and they’re cutting him off now to protect his health.