Australia is the smallest continent in the world. It is a little smaller than China. It is on the Southern Hemisphere of the earth. Australia is big, but its population is small. The population of Australia is nearly as large as that of Shanghai.

    Enough laws have been made to fight against pollution. The cities in Australia have little air or water pollution. The sky is blue and the water is clean. You can clearly see fish in the rivers. Plants grow very well.

    Last month we visited Perth, the biggest city in Western Australia, and went to a wild flower exhibition. There we saw large numbers of wild flowers on show, most of which we had never seen before. We had a wonderful time. Perth is famous for its beautiful wild flowers. Every year in spring Perth has a wild flower exhibition. After visiting Perth, we spent a day in the countryside. We sat down and had a rest near a path at the foot of a hill. It was quiet and we enjoyed ourselves very much. When we heard bells ringing at the top of the hills, we looked up, but what we saw made us pick up all our things and run back to our car as quickly as we could. There were about three hundred sheep coming towards us along the path.

    Australia is famous for its sheep and kangaroos. After a short drive from any town, you will find yourself among the white sheep. Sheep, sheep, everywhere you can see sheep.

    On the third Sunday in June, Americans take time to recognize and thank a special person in the family -fathers! Father's Day celebrates the importance of fathers, young and old and the men thought of as father figures.

    The words "the child is father of the man" come from William Wordsworth's poem My Heart Leaps Up. "It means people's personalities form when they are children. They will most likely have the same qualities as an adult that they had as a child.

    Used in everyday speech, one could say, "In his case, the child was father of the man; he loved nature as a child and now works as a botanist(植物学家)".

    Let's say you want to tell a child a story about something that happened long before they were born. You could say it happened when they “were just a twinkle in their father's eyes.” This expression has a humorous and dreamy feel. Here, the word “twinkle” suggests the interest your father had in your mother.

    When a much older man is interested in a much younger woman and supports her with his money, he is called he “sugar daddy.” The money part is very important-that's the sugar.

    Sometimes fathers are not a good influence or active in the lives of the children. In that case, a person may look for a father figure, a man who is not actually the person's father but who acts like one.

    The relationship between a man and his son can be complex. But the relationship between a father and daughter is often simpler. The expression “daddy's little girl” is understood to mean that, in a father's eyes, his daughter can do no wrong.

    There is usually not a dry eye at any wedding during the traditional father-and-daughter dance, especially if they are dancing to a song like Michael Buble's “Daddy's Little Girl.”

    Selena Gomez and I are scheduled to meet at a low-key coffee shop in Encino. Not wanting to keep the superstar waiting，I arrived at nine,20 minutes early. As I was catching up on e-mails，Selena quietly scooted into the seat next to me. No bodyguard. Not even a drop of make-up. She was ten minutes early and so inconspicuous that no one else in the restaurant looked up so much. Elena was wearing Bebe shorts. She had a baby face and ordered a hot chocolate.

    After making a small talk about what she wore for the shoot，she dived into the subject of her career. Elena declared 2012 the year of movies. She filmed three：SpringBreakers ， a drama；The  Getaway ， an action flick；and HotelTransylvania ， a comedy. Each is a marked move away from the teen style that made her a household name.

    Now that her Disney days are behind her，Selena is at that unstable point in a child star's career where she is trying to grow up—both as a person(she turned 20 in July) and as an artist. "Being part of the Disney Channel was such a blessing，and I'm super happy with what my show accomplished，but acting is something I would like to take on more seriously." She continued，"I don't necessarily feel accomplished. I want to create a whole different persona when it comes to acting."

    Selena has been working full-time since she was seven years old and scored a role on Barney & Friends. In 2007 when she was offered the lead in WizardsofWaverlyPlace ， Selena，her mother，and her stepfather uprooted from Grand Prairie，Texas，to L．A.，where they are settling now.

    Fabien Cousteau was born with deep love for the ocean. His grandfather and his father were ocean explorers and documentary filmmakers. Fabien spent his early years on his grandfather's ships. Today Fabien follows in his family's footsteps to protect the planet's endangered ocean life. With his vast knowledge and experience, he tries to strike a balance between environmental problems and market economies.

    Fabien is well known for his study of sharks. During 2000-2002, he created a TV special called Attack of the Mystery Shark based on the shark attacks that occurred along the New Jersey shoreline in the summer of 1916. Then in 2003-2006, with the help of a large crew, Fabien created a shark submarine (潜艇) that enabled him to put himself inside the shark world, providing people with a rare view of the mysterious and often misunderstood creatures.

    For the next four years (2006-2010), Fabien was part of a series called, Ocean Adventures, which offered a rare look into some of the most fantastic ocean species (物种) and environments.

    In 2010, Fabien started Plant A Fish, a nonprofit project for children to help restore local water ecosystems by replanting key ocean species. Save the world, one fish at a time. The project is still in progress now and its final goal is to plant 1 billion "fish" worldwide.

    From June 1 to July 2, 2014, Fabien and his team spent 31 days underwater to research how climate change and pollution are affecting the oceans. Fabien's Mission 31 broke new ground by going deeper, longer and further, exposing (显露) the world to the adventure and the mystique (神秘) of what lies beneath.

    Fabien is currently working on a documentary film about the adventures of Mission 31, as well as building an Ocean Learning Center to provide children around the world with the opportunity to learn about oceans and engage with ocean explorers directly through social media.

    Sweet potato plants don't have spines or poisons to defend themselves. But some have evolved a clever way to let hungry herbivores (食草动物) know they aren't an all-you-can-eat buffet, a new study finds. When one leaf injured, it produces a chemical that warms the rest of the plant and its neighbors to make themselves inedible (不宜食用的)to bugs. Sweet potato breeders could potentially engineer plants to produce the chemical as an all-natural pest defense.

    Plant ecologists led by Axel Mithofer of the Max Planck Institute for Chemical Ecology in Jena, Germany, started to look into sweet potato (Ipomoea batatas) defenses after they noticed something interesting about two varieties of the plant grown in Taiwan: The yellow-skinned, yellow-fleshed Tainong 57 is generally herbivore-resistant, but its darker orange cousin, Tainong 66, is plagued (造成麻烦) by insect pests.

    To find out why, the team offered up Tainong 57 and 66 plants to hungry African cotton leafworm caterpillars (毛虫).Both plants released at least 40 airborne compounds as the caterpillars snacked on their leaves. But Tainong 57 produced a lot more of a chemical called DMNT, which has a very distinct smell, the team details this month in Scientific Reports. ("The smell is not nice," Mithofer says. "You wouldn't want it as a perfume.")

    DMNT isn't a new compound; researchers have isolated (分离出) the smelly chemical from other plants such as corn and cabbage, and it is known to induce defense responses in some species.

    To determine whether this was happening in sweet potatoes, scientists set up two experiments. First, they put two plants next to each other and wounded one so it produced DMNT. Then, they exposed healthy Tainong 57 plants to DMNT they had synthesized (合成).In both cases, the DMNT caused the exposed plants to produce more of a protein called sporamin in their leaves. (Tainong 66 did not have the same reaction.) When the caterpillar's snack on sporamin, "they immediately stop eating because they don't feel well," Mithofer says.

    Sporamin is the main protein in sweet potato tubers (块茎),and is indigestible raw, which is why sweet potatoes must be cooked for humans to enjoy them. "If the caterpillars could cook it, they could eat it," Mithofer says. Theoretically, he says, sweet potato breeders could use genetic engineering to make different varieties of sweet potato produce as much DMNT as Tainong 57, and display the same defense responses.

    Still, the research isn't ready for prime time, cautions plant ecologist Martin Heil. DMNT might work in the lab, but in the field, airborne chemicals can be "blown away in seconds," says Heil, who studies plant-insect interactions at the National Polytechnic Institute in Irapuato, Mexico.

    Mithofer himself has no plans now to create genetically engineered sweet potato plants, because they would not be a viable (能活下去的) crop in Europe, where genetically modified crops are outlawed. So for now, Tainong 66 will have to put up with being a caterpillar salad bar.

What is the best part of a typical relaxing summer day? Nothing is better than sitting in an armchair with a beer and some chips in your hand, enjoying the great comfort.

The much-loved combination of beer and chips is being exploited for the first time to deal with climate change. Chips firm Walkers has adopted a technique it says will cut CO₂ emissions (排放) from its production process by 70%.

The technology will use CO₂ captured from beer processing in a brewery (啤酒厂), which is then mixed with potato waste and turned into fertilizer. It will then be spread on UK fields to feed the following year's potato crop. Creating fertilizer normally produces high CO₂ emissions, but the technology adopted by Walkers makes fertilizer without generating CO₂. So, the beer-and-chips combination performs a double function. It stops the emission of brewery CO₂ into the atmosphere — and it saves on the CO₂ normally generated by fertilizer production.

This Creative win-win solution was developed with an approval from the UK government by a 14-employee start-up called CCm. The fertilizer was experimented on potato seed beds this year, and next year Walkers will install CCm equipment at its Leicester factory to prepare for its 2022 crop.

A decision has not yet been made on which brewery Walkers will work with on this. The new technology adds to carbon-saving techniques already under way. The firm has installed an anaerobic digester (厌氧消化池), which feeds potato waste to bacteria to produce a useful gas. The gas is burned to make electricity for the chip-frying process — so this saves on burning gas or coal.

The new system will go a step further by taking away potato "cake" left after digestion — and mixing the brewery CO₂ into it to make an enriched fertilizer which will help put carbon back into the soil as well as encouraging plant growth.

It's an example of scientists finding ways to use CO₂ emissions which otherwise would increase the over-heating of the planet.