You probably don't think about soil often, but the following report may help you learn about science of soil.

What is soil made of?

Soil is made of sediments (沉积物) and humus(腐殖质). Sediment is small pieces of rock broken down over time by rain, ice, and wind. Sediment is often found in water. Humus comes from decayed(腐烂的) plants and animals. It helps give plants a lot of the food they need to grow.

How does soil form?

Over centuries, rock breaks down into very small pieces.

The rock pieces mix with humus.

The humus gets thicker and thicker over time. Soil is formed(形成)l

How are soils different?

Soils can be different colors and have different textures(质感). Texture is how the surface of an object feels. Color and texture are two features(特征) of soil.

Plants and soil

Plants do not grow well in some soils. Sandy soi1 is too dry. It does not hold water. Soil with too much clay is too thick. Most plants grow well in dark, rich garden soil that has different sediments and a lot of humus in it.

    There is a man and he calls the police when he loses a pet. He a lways asks the police to help him look for it.

    “I lost my pet bird，”he tell the police one day.“She can sing songs. Can you find her for me?”

    “I'm sorry，”the policeman says.“It isn't our job（工作）to look for birds. If you leave a window open in your house，the bird may come back.”

    Another time，the man calls the police and says，“I lost my cat. （A）你能帮我找到他吗？He can  talk. ”

    “I'm sorry，”the policeman says.“（B）It isn't our job to look for cats. You should put the telephone down quickly. Maybe（也许）he is calling you now and tells you where he is. ”

    Liao Yifeng, a police officer working in a small village in Wuhan, is a "father" to 39 "left-behind" children, whose parents are working far away from home and seldom spend time with them.

    Wan Tianle, an 8-year-old boy, was the first to call Liao "Dad". Wan's parents divorced when he was only 6 months old. Ile never saw his mother again and his father later disappeared after getting into debt. When Liao learned that the boy couldn't even afford the 100 yuan monthly school living fees,   ①   , bringing 100 yuan.

    During last year's Mid-Autumn Festival, Liao carried a kilo of meat and pig's feet to his home. After dinner, the boy put his arm around Liao's neck and asked sweetly, "Uncle Liao, can I call you daddy?" Liao was deeply moved,    ②   .

    With a 2-year-old son of his own, Liao said he knew how important a father's love was to a child.

    In Wan Tianle's school, there are 407 left-behind children. With the help of teachers, Liao knows clearly each child's home conditions and pays more attention to the 39 children whose families are the poorest.

    Liao has built a special room named "family love room" in the police station, where Liao helped these left-behind children with their homework and taught them about safety in his spare time.

    Moreover, a computer in the "family love room" plays an indispensable role because it offers a precious opportunity for Liao to help children whose parents are working far away to chat with them online.

    It is said that everyone has two boxes hung on our necks. The small box at the front is full of other people's mistakes, while the big one at the back is filled with our own shortcomings(缺点).Most of time, it's easy to find other people's mistakes. It's hard for us to see our mistakes behind us.

    A boy called Tony, always looked at the front box to check what was in it. He saw other people's mistakes very quickly. When Ben was impatient with him, he said to Ben, "It's so easy for you to get angry. It is hard to be friends with you."

    He told his mother that Michael was dishonest. "Michael takes my things without asking. And he forgets to return them. "Tony himself did not like sharing his things with anyone.

    When John was too tired to go hiking with him, he said, "You are such an unfriendly person."

    He thought Nick was too proud of his rich parents. But Tony was so proud of himself because he could not see any of his own mistakes!①He could not understand why he didn't get on well with others. Then his mother said to him, "If you change the boxes around, maybe you can find the answer." He did it as his mother said, and his face turned red.②他发现自己并不比其他同学更好.