Our skin(皮肤) is like a bag that we live in. Inside the bag,     1    . Our water is like the water in the sea. It is very salty. Also, like the ocean, we can lose our water. The sun could take it away. Our bag of skin keeps our body’s ocean from drying up.

Our skin keeps out sunshine.    2    Skin also keeps out dirty things. That’s important because some kinds of them can make us sick.    3    . It feels warm things, cold things, things it touches, and things that hurt it. A fire feels warm. A snowball feels cold.

Our hair helps keep things out of our eyes, ears, and nose. Hair is also good for keeping us warm. When we get too cold, our body hairs stand up and hold air close to our skin like a heavy quilt.    4    . Some animals have more hair than others, so they are not afraid of cold weather.

Our nails(指甲) are another special skin which are very hard.    5    . Our nails aren’t as strong or sharp as the nails that animals have. But they are just good for the basic human needs.

【推荐3】Everything has a name. All people, places, and things have names. Jenny is the name of a student from the UK. The UK is the name of a country. Cities and towns have names, too. Schools also have names. Tomato, potato and carrot are names of vegetables. Apple, orange, and banana are names of fruit.

When we meet a new person, we usually ask, “What's your name?” Most people have two names. Names are different all over the world. In Jenny's class, Jenny must know the names of the students from all over the world. This is not easy because the names are very different.

In the USA, most people have a first name, a middle name and a last name, Parents choose(选择) the first and middle names for their babies. The last name is the family name. Usually it is the father's family name. In a family, the mother, the father, and the children usually have the same last name.

Sometimes a person has a nickname(绰号), too. A nickname is a special(特殊的) name. It's not a person's real name. Abraham Lincoln's nickname was “Honest Abe”, because he was honest(诚实的) and Abe is short for(…的简称) Abraham. Pele is a nickname of the football player, Edson Arantes do Nascimento. But everyone calls him Pele.

【推荐3】Li Ruyan, 13 years old, did something special last summer with his classmates in Shanghai. They worked in groups with traffic police at different crossroads in the city. Holding small red flags, the students helped keep order and stopped people from jaywalking (乱穿马路). As part of the school project, Li’s school has encouraged its students to do more community (社区) work. After the half day of exhausting work, Li told himself not to jaywalk anymore.

“I think through community work we get to help others and, more importantly, we grow a sense of responsibility (责任感),” he said.

Community service is an important part of education for teenagers around the world. In the US and Canada, high school students need to finish 40 hours of community service before graduation. In America, those who have finished 1,400 hours of community work can be awarded nearly $5,000 (33,000 yuan).

Chinese students today do more community work, too. For example, starting from 2010, Sichuan high school students have been asked to do 10 days of community work. It will become part of their school grades.

Qian Lijun, 16, and her classmates in Suzhou, Jiangsu went to a local elder care home this winter. They put Spring Festival couplets (对联) on the walls and cheered up the people living there.

Li Xiaotian, 15, in Anshan said he used to clear flyers (小广告) from telephone poles (电线杆) with his classmates. They brought tools, towels and buckets and worked for three hours under the summer sun. “It was tiring, but seeing the clean poles without ugly ads, we really felt proud,” he said.