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We have English classes from Monday to Friday. So Grace is very busy. But she is always nice and happy. All my classmates like her and her classes very much. She often plays English games and sings English songs with us. When we have questions, we like to ask hat for help.

Now I think I can do well in English because I have the best (最好的) English teacher, Grace.

Because of the fast pace of social life, a good sleep is sometimes beyond our reach. Maybe you didn't get enough sleep last night, but chances are you're still doing better than the (type) northern elephant seal. Scientists (discover) the massive creatures are often getting less shut-eye than most others in the animal kingdom recently.

For months at a time, they go on long voyages they migrate thousands of miles off the Pacific coast and back again as they hunt for food. While out at sea, they're (continuous) diving more than 3,000 feet underwater. "So there's a bit of a puzzle," explains McKnight. " you're diving all the time, and spending 90% of your time at sea underwater without access air, when do you sleep?"

study published on Thursday in the journal Science now offers an answer: Northern elephant seals rely on short power naps during those deep (dive), which altogether add up to about two hours of sleep per day, says Jessica Kendall-Bar, the study's lead author and an eco-physiologist at Scripps Institution of Oceanography. "And they do that while (hold) their breath very deep below the ocean surface," she says.

The new findings mean that northern elephant seals now beat African elephants who currently hold the world record for the (short) daily sleep time among mammals.

She had asked the government for5 to move the books to a safe place, but they refused. So Alia took matters into her own hands6 . She brought books home every night,7 her car late after work. Her friends came to help her when the war broke out. Anis who owned a restaurant8 to hide some books. All through the nights, Alia, Anis, his brothers and neighbors took the books from the library,9 them over the seven-foot wall and hid them in the restaurant. The books stayed hidden as the war10 . Then nine days later, a fire burned the11 to the ground.

One day, the bombing stopped and the12 left. But the war was not over yet. Alia knew that if the books were to be13 , they must be moved again while the city was14 . So she hired a truck to bring all the books to the houses of friends in the suburbs. Now Alia waited for the war to end and15 peace and a new library.

The researchers brought 28 horses into a room one by one, each wearing heart rate monitors as their actions were recorded. The horse faced two screens playing two different videos: one showed a happy person and the other a sad person. A voice was played at the same time, sounding happy or sad.

When the picture and voice didn't match—for example, if the voice was sad but the picture showed a happy person—the horse seemed puzzled and looked for a longer time, compared to the one that did match, as if it knew something didn't make sense. "You could imagine that they have a particular box in their mind labeled ‘human sadness' containing the characteristics of both a sad face and a sad voice, and that when we are sad, they expect what we say to match how we look," said Doctoral Researcher Océane Liehrmann of the University of Turku, in Finland.

The researchers also saw that horses were more attentive to the screen displaying the happy face. They looked at it more often and for a longer time and their heart rates increased when they heard a happy voice and decreased when they heard a sad voice as well.

It is possible that the horses might have associated happy human expressions with positive memories from their past. Another theory is that seeing a happy person could actually make a horse feel happier—a process known as emotional contagion. "We don't know whether horses themselves understand what it is to be sad. It is possible that they learn it means something for a human," said Liehrmann.