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.

    Six million people visit Grand Canyon in the US every year. For the purpose of helping project Grand Canyon for your fellow visitors and future generations, please follow the guidelines below.

    Camping

    To protect the park, camping is allowed only within permitted campgrounds. Permits are required for overnight camping at the North Rim. Advance booking can be received by mail. Please write: Information Center, P.O. Box 129, Grand Canyon, AZ 86023.

    Fires

    Because of the extreme fire danger, campfires are not allowed except at Mather and Desert View campgrounds. Collection of firewood is not allowed either.

    Hiking（远足）

    Please stay on permitted paths. Otherwise you may destroy desert plants. Pack out what you pack in, so you leave no signs of your visit. It is important to keep in mind that you are in a national park where wildlife exists.

    Weather

    The weather at Grand Canyon can change very quickly. With so much rock, lightning(闪电) causes a particular danger during sudden summer storms These storms also frequently bring floods inside valleys, a danger to hikers. Watch the skies and check daily weather reports.

    Wildlife

    Do not feed park wildlife. There have been a few cases at Grand Canyon National Park where deer(鹿) were purposely shot because there are plastic bags that left them sick and weak. Hungry deer car be danger and have kicked and bitten visitors at Grand Canyon. Some other animals will also beg and bite. For your own safety and the well-being of the animals, please do not feed wildlife, no matter how gentle they may appear.

    Look and listen, and that concert poster just might be singing. Engineers have designed antennas（天线）that can turn everyday objects, from posters to clothing, into radio stations. Anyone walking or driving by can tune in and hear what's on. The devices use radio waves, but they don't generate their own. They hijack（劫持）the same waves that carry music and news to your smartphone.

    Vikram Iyer co-led the project with Anran Wang, a graduate student in computer science and engineering. The two got the idea for their invention by paying attention to what was already around them. “It's the ideal way to minimize the power consumption for any kind of communication,” notes Iyer. Their research had focused on new types of wireless communications that won't require much energy. They wanted something that would work outdoors in a city. Then they realized the air is already filled with wireless communications in the form of radio stations.

    Radio waves carry energy at the speed of light from tall transmission towers to radios in cars, phones and homes. These waves of the antennas take in existing radio waves and change them slightly. Those changes add new sound information. The changed waves are then sent back out into the world where people can listen in. So the device only needs enough power to change the waves, not to generate them.

    The scientists tested their device with a poster. It advertised a Seattle concert by Simply Three. People standing almost 4 meters away from the poster could use FM receivers on smartphones to listen to all songs of the band's music. Those in cars as far as 18 meters away could use car radios to pick up some parts of the songs

    The technology could even extend to clothes. Iyer, Wang and their team turned the shirt into an antenna. It let the shirt talk to the wearer's smartphone. If a sensor in the shirt tracked a person's heart rate during exercise, for instance, the antenna could transmit those data to the wearer's phone.

    Everyday Food—--by Martha Stewart

    No matter how busy you are, at the end of the day you want meals that are easy to prepare. And you want lots of choices and variations. You'll find all of that in this book: 250 simple recipes for delicious meals that bring freshness and nutrition.

    Paperback, published by Random House, $ 16.79

    Zeroes —--by Scott Westerfeld, Margo Lanagan and Deborah Biancotti

    New York Times bestselling author Scott Westerfeld teams up with Margo Lanagan and Deborah Biancotti in the book about six teenagers with amazing abilities. These teenagers have powers that set them apart. They can do things ordinary people can't.

    Paperback, published by Simon & Schuster, $12.99

    Mighty Jack —--by Ben Hatke

Jack dislikes summer. But he's got a good reason: summer is when his single mom takes a second job and leaves him at home to wa tch his sister, Maddy. It's lots of responsibility, and it's boring, too, because Maddy doesn't talk. But one day, at the market, Maddy does talk—to tell Jack to trade their mom's car for a box of mysterious seeds. It's the best mistake Jack has ever made.

    Hardcover, published by First Second, $ 14.15

    Only Daughter —--by Anna Snoekstra

    She's caught stealing. She's homeless and on the run. But she happens to look the same as a girl who went missing a decade ago, Rebecca Winter. She assumes (冒充) Rebacca's identity, using it as a way out.  She doesn't know anything about her new life as Rebecca is itself a prison and it looks like a killer might be after her.

    Kindle edition, published by Harlequin Enterprises, $8.88

    It's a white Christmas in the United States today, with snow falling from Seattle to Maine.

    •Northeast

    Biting winds with snow swept the Northeast.

    Earlier, up to 15 inches of snow fell during a snow storm in Maine, while up to one foot fell in New Hampshire. Winds reached 76 mph on Cape Cod, Massachusetts, while up to 61 mph winds tore through Long Island, New York. Falling snow collected on the runways at Boston's Logan International Airport, causing temporary flight delays.

    The wind was so severe in Pennsylvania and New Jersey that the annual (重演) of George Washington and his soldiers' crossing the Delaware River was canceled, the Washington Crossing Historic Park told ABC News.

    •Midwest

    Heavy lake effect snow fell in western Michigan.

    The National Weather Service has issued a wind-chill warning and advisory (公告) from Montana to Michigan. Bitter cold air in the Midwest produced wind chills Monday morning as low as minus 48 degrees in North Dakota and minus 47 in northern Minnesota.

    As this bitter cold made its way east overnight, it was expected to move over relatively mild Great Lakes, producing intense lake-effect snow bands capabie of producing 2 to 4 inches of snow in an hour.

    •West Coast

    That storm system moved overnight through the Rockies, bringing more snow and the threat of avalanches (雪崩). The National Weather Service has issued an avalanche warning for the Wasatch Range Mountains outside Salt Lake City.

90 percent of the world's fireworks are produced in China. The biggest importer is the US, which {#blank#}1{#/blank#} (ship) in more than US $650 million worth in 2021.

The details of fireworks' invention are lost to history, but {#blank#}2{#/blank#} folk tale tries to fill in the gap. It goes that monk named Li Tian created fireworks around 1400 years ago by packing gunpowder into bamboo tubes {#blank#}3{#/blank#} (scare) off evil spirits.

An explosive mixture of gun-powder and chemical compounds (化合物) is {#blank#}4{#/blank#} makes fireworks flash in pretty colours and fun shapes. The images they make depend on the placement of these compounds inside the shell of the firework. Crowd {#blank#}5{#/blank#}(favorite) include "comet", featuring a long trail of sparks; "peony", a flower-like burst; and "strobe", which produces a blinking effect.

The single biggest firework shell ever shot was part of a 2020 winter-carnival display in Colorado, US. {#blank#}6{#/blank#} (weigh) 1268 kilograms, it rose more than a kilometre into the sky {#blank#}7{#/blank#} bursting, turning the night sky red.

For centuries we had to light firework {#blank#}8{#/blank#} hand, but since the 1980s, there's been another option: computer-controlled lighters, which made music at displays more {#blank#}9{#/blank#} (precise) timed and safer. An even greener alternative recently {#blank#}10{#/blank#} (adopt) is using drones to trace flashy patterns in the sky. The future of fireworks, like so much else, may be robotic.