On a hot summer day, there are few things that are more wonderful than a nice cool pool.

    {#blank#}1{#/blank#}And it is completely relaxing. Of course, if you have children, there are certain measures you should take to keep them safe, whether you have a pool in your backyard or you are going to a public pool.

    People should never swim by themselves. Actually it only takes a second for people to become injured and drown(溺水). {#blank#}2{#/blank#}This is especially true for young children.

    Splashing(玩水) is fun, but don't take it too far. {#blank#}3{#/blank#}Kids love to go after one another through the water and to splash and jump around. But it is important to teach children not to jump on top of one another and to watch their surroundings in the water, so that they do not accidentally knock into others.

    If you have a pool, you must have a locking gate around your pool. {#blank#}4{#/blank#}Keep the gate knocked at all times, even when you are in the pool.

    Know the way out. {#blank#}5{#/blank#} Make sure that they know where all ladders are and how to enter and get out of the pool properly. Although your children may be able to lift themselves out of the pool using the side, that is not the safest way to go.

A.Kids should be taken good care of when they are swimming in the pool.

B.This is to prevent children from entering your pool without your knowledge.

C.And having someone there with you can make the difference between life and death.

D. Be sure to show all children the proper way to get out of the pool.

E.Even so, attempt to avoid getting any pool water into your mouth.

F. Jumping into the water seems like the perfect way to deal with the heat.

G. .Playing around in the pool can be a lot of fun.

    A new article in The Wall Street Journal has given us a deeper understanding of the relationship between what we earn and how we feel.{#blank#}1{#/blank#}Well,not true.People with higher incomes are happier than those who struggle to get by.To put a smile on your face with your money,you need to spend it strategically.Here are some ways to better spend your bank notes.

    Buy experiences,not material things.

    {#blank#}2{#/blank#}People think that experiences are only going to provide temporary happiness,but they actually provide both more happiness and more lasting value that help you better manage your life.

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    Anything you buy,including a product you think is special will become just another object.Buying small things can give us frequent small pleasures that are different each time they occur,as they forestall（抢先）adaptation.

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    It's also important to consider how what you're buying will affect how you spend your time.For example,you may have to spend a very long time on the road if you get a big house in the suburb,which will totally lower overall life satisfaction.

    Try giving it away.

Elizabeth Dunn,associate professor of psychology at the University of British Columbia in Canada,found that in countries as diverse as Canada,South Africa and Uganda,giving away money consistently made people happier. {#blank#}5{#/blank#}A.Buy what you like.

B.Be sure to buy time,too.

C.More money,more smiles?

D.Money can't buy happiness,right?

E.Buy lots of little things,rather than one big thing.

F.With no much money to spare,people tend to stick to material goods.

G.This was even true for people who were ly poor themselves.

    One of the most important aspects of an image is color. People are very sensitive to color, and different colors have different on people.

    In general, red is an exciting color, which creates an image of action, energy danger. Red is also the most frequently used color in flags. Eighty percent of the world's flags contain red. A study in Germany showed that football teams wearing red are more successful. Blue is a very calm color. Business executives usually wear dark blue suits. Blue is also a peaceful color. The flag of the United Nations is light blue. Yellow is associated with openness and freedom. Green is a very relaxing color. Surgeons nowadays wear green, because it's less tiring than white. Black creates an image of power and authority. It can also be a very threatening color. Gangsters and vampires often wear black, white is a pure and strong color. This is one reason why doctors wear white coats. We trust them more. Grey is a very anonymouscolor. People wearing grey don't want other people to notice them. Brown is the opposite of black. It's warm and friendly, while black is threatening

    While we all try to find happiness, sometimes we still end up feeling low. While most people can control this feeling, low moods can stay with some, leading to depression. About 322 million people suffered from depression in 2015, according to a report by the World Health Organization in February. This is more than 4 percent of the world's population.

    Depression is described by the WHO as a mental disorder. It has several symptoms including sadness, loss of interest and feelings of low self-worth. In severe cases, depression may even lead to suicide.

    The number of people living with depression is increasing. The WHO reported a rise of 18.4 percent between 2005 and 2015. Young people are a group known to suffer with depression. “The pressures on today's youth are like no other generation, perhaps," Dan Chisholm, an official of WHO, told Reuters.

    In China, depression among young people is on the rise, Zhu Zhuohong, a psychology professor with the Chinese Academy of Sciences, told Xinhua News Agency. Competition to outperform others, especially in education, can cause a lot of pressure for Chinese youth.

    Almost 1.2 million Chinese people aged 15 to 24 suffer from depression, according to a report released by British science journal The Lancet in May.

    Luckily, more and more efforts are being made to deal with this problem. This year's World Health Day, held on April 7, will focus on depression. The day will highlight the “Depression: let's talk" campaign. The campaign aims to make sure that people with depression both seek and get help.

    Fashions have a lot of rules. Most of them, however, are just wrong. But there's one rule that goes beyond tradition and into the field of scientific study of the brain: Black clothes are slimming. It all comes down to how your visual system processes the light. The below holes in each square are the same in size, yet the white hole looks bigger than the black hole.

    In the 1500s, Galileo Galilei noticed that some of the planets looked larger when viewed with the naked eye than they did when viewed through a telescope, making the white light of Venus appear eight to ten times larger than Jupiter in the night sky. He knew something strange must be going on with his vision to cause this illusion, but he wasn't sure what it was. Luckily, scientists never stopped wondering, and in 2014, they figured it out.

    Our visual system operates via two main channels: "on" neurons (神经元) that are sensitive to light things and "off" neurons that are sensitive to dark things. When it came to the dark "off" neurons, the researchers found that they responded predictably to dark shapes on a light background the greater the contrast between the two, the more active these neurons were. But the light on" neurons behaved unpredictably. Even with the same amount of contrast, light objects on a dark background caused a greater response in these neurons.

    This phenomenon makes some sense, evolutionarily speaking. In the dark of night, you'd want to be able to take in every bit of light you can get, so a visual system that enlarges light objects on a dark background could be very useful. However, it's not that hard to see dark objects in the light of day. It has some effects in the colors of your clothes and in the appearance of the planets—the brighter appearance of Venus in the night sky makes it look bigger than the darker Jupiter.

    Most dog owners have probably been puzzled waiting for their dog to do its business. Instead of just finding a soft area of grass to go number two, they make a whole ritual(仪式) out of it, spinning in a circle before finally squatting(蹲下). Luckily, the ultimate pet owners' question may finally have been answered.

    A few theories have circulated about why dogs might circle before pooping  and most are similar to the reasons they spin before lying down. Trampling around in a circle would flatten the grass around, which would keep tall blades(叶片) from trapping their waste. Another explanation could be that they're scanning for snakes and predators before they become completely occupied.

    But Czech researcher Hynek Burda didn't quite buy into those theories. Dogs evolved from wolves, which didn't need to worry much about tall grass. And if they were scanning their environment, keeping still to listen and sniff would be more effective than giving the area a quick once-over. Instead, Burda suggested that dogs spin to get a feel for the Earth's magnetic pull.

    The Earth has a magnetic field around it protecting it from radiation from space, and some animals seem to use it to get a sense of where its North and South poles are. For instance, it's how birds know which way to migrate. In 2013, Burda published a study in the journal Frontiers in Zoology suggesting dogs have a strong internal compass, too. He and his team spent two years watching 70 dogs poop and pee and recording which way they faced and how strong the magnetic(磁的) field was.

    As it turns out, when the magnetic field was calm, dogs preferred to poop facing either north or south.

    The pattern couldn't explain why dogs like facing the Earth's poles, but the researchers think it might help them remember where they marked their territory.

    If they can remember which way they were facing, they might find it easier to find that spot again. So before you roll your eyes when your dog takes ages to do his business, remember that Fido might just be getting scientific about his potty spot.