My school stood in a big square playground in southeastern South Dakota. One teacher taught all grades, first through eighth. Most grades had only two or three students.

    Our school day started with the flag pledge(宣誓). Then the teacher called one grade at a time to the recitation bench beside her desk. She'd check our work, explain the new lesson, and dismiss us to go back to our own desks and do our new work, all in less than ten minutes per grade.

    At noon we ate lunches we had brought. Our lunches consisted of homemade sandwiches and if we were lucky, dessert. My favorite dessert was a fresh pear, and a piece of Mom's delicious sour cream chocolate cake.

    The annual Christmas program was the most exciting part of the year. We hurried through our lessons during December to allow time to practise poems, songs, and plays.

    A few days before the performance, the school board members borrowed equipment from the town and set up a stage across one side of the classroom. We hung bed sheets for curtains.

    On the evening of the performance, petrol lanterns hanging along the walls cast a warm, though not very bright, light over the gathering crowd. We could hardly contain our excitement as we looked from behind the curtains to wave at our parents.

    On a spring Sunday in a new term, just before the last day of the school term, everyone in the neighborhood gathered for a picnic. Our moms set fried chicken, bowls of salads, and desserts on the teacher's desk and the library table. After the dinner, we played games. One of the school board members brought big buckets of ice cream in the afternoon to top off the picnic. How we looked forward to that treat!

    I was just nineteen years old when I started my first teaching position in a country school with thirteen students. I felt excited, nervous and happy as I prepared my lunch bucket the first morning of the term. I can't remember what kind of sandwiches I packed, but I do remember I put in a fresh pear and a piece of chocolate cake for dessert!

    After a confirmed rabies(狂犬病) case in Parke County, Indiana, experts are urging caution if you find a bat(蝙蝠) in your home or office.

    “If you try to kill a bat, you are more likely to get bitten,” said Joy O'Keefe, assistant professor of biology and director of Indiana State University's Centre for Bat Research, Outreach and Conservation. “Most bats people find in their houses are healthy and are not going to bite them and give them rabies.” But they could be a federally endangered species, such as the Indiana Bat, which is found in this area.

    So if you spot a bat in your home or office, don't kill it or touch it with bare hands, O'Keefe said. Instead, put on a pair of heavy gloves and gently move it into a box or bucket. Once contained, the bat can be removed outside.

    “If it's a healthy bat, it'll fly away eventually,” O'Keefe said. “If it doesn't move or seem to be healthy, you can take it to the health department to be tested.”

    This is the time of year when bats move from their summer resting sites to their winter resting sites, O'Keefe said.

    “We get calls every year during the first month of school year from people finding bats in the university's buildings,” said O'Keefe.

    Bats are a great help to people, as every night they can eat up to their entire body weight of insects. Bats, however, are facing great threats from epidemics(流行性疾病), habitat destruction and other things.

    “The best way the average person can help bats is by understanding them and by telling other people how awesome bats are and what bats do for us,” O' Keefe said. “Hopefully, it will make people think that if there's a bat in their house, they should try to get it out but not kill it. That would be really positive for bats—to not have people be one of their major threats.”

What brings a nation together? Of the four choices — shared values, language, history, and religion, it's shared values. In our latest poll (民意调査), seven out of 16 countries chose values as the greatest factor (因素）bringing a nation together, and six preferred language. Both choices scored high in the poll, suggesting that our values and how we express them are closely linked Still, history was not forgotten in some countries, particularly in Mexico and Russia. Even Canada and the United States chose national histories as the second-most important factor uniting their people. The biggest surprise? Not one country picked religion as its top choice.

    If you are a fruit grower—or would like to become one—take advantage of Apple Day to see what's around. It's called Apple Day but in practice it's more like Apple Month. The day itself is on October 21, but since it has caught on, events now spread out over most of October around Britain.

    Visiting an apple event is a good chance to see, and often taste，a wide variety of apples. To people who are used to the limited choice of apples such as Golden Delicious and Royal Gala in supermarkets, it can be quite an eye opener to see the range of classical apples still in existence, such as Decio which was grown by the Romans. Although it doesn't taste of anything special，it's still worth a try，as is the knobbly(多疙瘩的) Cat's Head which is more of a curiosity than anything else.

    There are also varieties developed to suit specific local conditions. One of the very best varieties for eating quality is Orleans Reinette, but you'll need a warm, sheltered place with perfect soil to grow it, so it's a pipe dream for most apple lovers who fall for it.

    At the events, you can meet expert growers and discuss which ones will best suit your conditions, and because these are family affairs, children are well catered for with apple­themed fun and games.

    Apple Days are being held at all sorts of places with an interest in fruit, including stately gardens and commercial orchards(果园)．If you want to have a real orchard experience, try visiting the National Fruit Collection at Brogdale，near Faversham in Kent.

    On April 2, we said goodbye to Tiangong I, China's first space lab. According to the China Manned Space Agency（中国载人航天）, Tiangong I re-entered the Earth's atmosphere （大气层）and fell into the South Pacific Ocean.

    There are many spacecraft that are still in orbit above the Earth. They are flying at heights ranging from 300 to 1,000 kilometers. After finishing their trips, they will all re-enter the Earth's atmosphere like Tiangong I.

    There are two types of re-entries：controlled（受控的）re-entry and uncontrolled re-entry.

    Some satellites（卫星）and manned spacecraft come back to the Earth in a controlled re-entry. Scientists calculate（计算）the path of the falling spacecraft and its speed. They can guide the spacecraft to fall in a chosen area. In 2017,Tianzhou I, China's first cargo（货运）spacecraft, was directed to fall in the South Pacific Ocean.

    Some spacecraft may have problems while in space, or are simply no longer usable after a certain amount of time.  These craft come back in an uncontrolled re-entry.  It is hard to tell when and where these spacecraft will fall until the last few hours. The US space station Skylab came back partially uncontrolled in 1979. Parts of the station fell in western Australia, but no one was injured.

    During re-entry, most of the spacecraft will burn up while passing through the Earth's atmosphere. Only a small amount of the debris（碎片）will reach the ground.

    The debris typically ends up falling into the ocean, China Daily reported. Tiangong I weighs about 8.5tons. The amount of debris that falls to the Earth might be about 1 to 1.5 tons, the Beijing News reported.  That is about the same weight as a car.

    Twenty-one years ago, my husband gave me Sam, an eight-week-old schnauzer（雪纳瑞犬）, to help ease the loss of our daughter. Sam and I developed a very special bond over the next years.

    At one point, my husband and I decided to move to a new home in New Jersey. Our neighbor, whose cat had recently had kittens, asked if we would like one. We were a little apprehensive about Sam's jealousy and how he would handle his turf（地盘）being invaded, but we decided to risk it.

    We picked a little, gray, playful ball of Fur. She raced around chasing imaginary mice and squirrels and jumped from table to chair in the blink of an eye, so we named her Lightning.

    At first, Sam and Lightning were very cautious with each other and kept their distance. But slowly, Lightning started following Sam — up the stairs, down the stairs, into the kitchen. Later, when they slept, it was always together; when they ate, it was always next to each other. When I took either one out, the other was always waiting by the door when we returned. That was the way it was for years.

    Then, without any warning, Sam was diagnosed as having a weak heart. I had no other choice but to have him put down. The pain was nothing compared with what I experienced when I had to walk into our house alone. This time, there was no Sam for Lightning to greet and no way to explain why she would never see her friend again.

In the following days, Lightning seemed heart-broken. I could see the disappointment in her eyes whenever anyone opened the front door, or the hope whenever she heard a dog bark.

    One day as I walked into our living room, I happened to see Lightning was lying next to the sculptured replica（复制品）of Sam that we had bought a few years ago, one arm wrapped around the statue's neck, contentedly sleeping with her best friend.