2 . Atomic shapes are so simple that they can’t be broken down any further. Mathematicians are trying to turn to artificial intelligence (AI) for help to build a periodic table of these shapes, hoping it will assist in finding yet-unknown atomic shapes.

Tom Coates at Imperial College London and his colleagues are working to classify atomic shapes known as Fano varieties, which are so simple that they can’t be broken down into smaller components. Just as chemists arranged element s in the periodic table by their atomic weight and group to reveal new insights, the researchers hope that organizing these atomic shapes by their various properties will help in understanding them.

The team has given each atomic shape a sequence of numbers based on its features such as the number of holes it has or the extent to which it bends around itself. This acts as a bar code (条形码) to identify it. Coates and his colleagues have now created an AI that can predict certain properties of these shapes from their bar code numbers alone, with an accuracy of 98 percent.

The team member Alexander Kasprzyk at the University of Nottingham, UK, says that the AI has let the team organize atomic shapes in a way that begins to follow the periodic table, so that when you read from left to right, or up and down, there seem to be general patterns in the geometry (几何) of the shapes.

Graham Nib lo at the University of Southampton, UK, stresses that humans will still need to understand the results provided by AI and create proofs of these ideas. “AI has definitely got unbelievable abilities. But in the same way that telescopes (望远镜) don’t put astronomers out of work, AI doesn’t put mathematicians out of work,” he says. “It just gives us new backing that allows us to explore parts of the mathematical landscape that are out of reach.”

The team hopes to improve the model to the point where missing spaces in its periodic table could point to the existence of unknown shapes.

3 . Fresh fish should have a mild smell. Strong fishy smells are the first signs to go bad. How do the fishy smells come from?

It can be several days from when the fish are caught to when they reach the supermarket. In that time, bacteria that grow naturally in fish start to consume a substance called trimethylamine N-oxide(TMAO)in fish. These bacteria change TMAO into trimethylamine (TMA), the substance responsible for the fishy smells. Bacteria in fish can also change lysine(赖氨酸)into cadaverine(尸胺), a substance that’s associated with breaking down the fish once they are caught and giving off fishy smell.

Chemical reactions can also lead to fishy smells. This happens through the oxidation(氧化)of fat. Fish are an important source of omega-3 fatty acids. When these fats are exposed to oxygen, they oxidize and break down into the substance that you can smell.

To slow down the fishy smell, what is beyond question is that the less time between when the fish are caught and when they reach the kitchen, the better. But today, fish are often flown across the globe. To keep smell-producing bacteria at bay, the fish must be frozen or kept at the low temperature possible as soon as they are caught and cleaned.

Controlling fat oxidation can function as well, especially for fattier fish species. While freezing slows bacterial growth, it does not stop fat oxidation. This reaction will occur as long as oxygen is present. Fatty fish are usually not frozen because, despite the cold temperature, they’re going to oxidize pretty fast unless they are stored in a low oxygen container. That’s why those species are often canned.

It’s also important to remember that smell is not always an indicator of safety, especially in processed fish products. “What you might consider the fishy smell may be a delicacy in another culture,” said Carl A. Batt, a professor of food science at Cornell University.

4 . How to Design a Small Garden

Even if you don’t have a large area in your yard, you can still make a beautiful garden that maximizes the space you have by following tips.

    1    . Look for a place in your yard where you can see your garden from a window or a spot in your yard so that you’re able to enjoy it. Make sure you can walk into your garden with ease to make it easier to take care of your plants.     2    .

Plan the layout for your garden by drawing the outline on the paper. Start by sketching longer rectangles（矩形）for your garden beds so they’re to scale for the actual size you want them.     3    . Be sure to leave an 18-inch space between garden beds so you can easily walk between them and care for your plants.

Arrange your design so there are focal points. Aim to have several aspects of your garden design unique so they stand out from the rest of your plants.     4    . Take into consideration where you want people to focus or have their attention drawn to when they look at your garden, and plan your design around those spots. Focal points help your garden feel more inviting and make it more visually pleasing.

Put similar plants across from one another to create rhythm and symmetry(对称). Rather than put different plants in each of your garden beds, choose to use the same plant or ones that have similar textures or colors so they’re across from one another.     5    .

7 . 假定你是李华，你的美国好友Susan下周要参加国际中华思想文化演讲比赛（International Speech Contest on Chinese Thought and Culture），给你发来邮件表示焦虑、紧张。请你就此给她回封邮件，内容包括：

1.表示宽慰；

2.提出建议；

3.给予鼓励。

注意：

1.词数80左右；

2.格式已为你写好。

Dear Susan,

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Best wishes,

Li Hua

That’s all for my presentation. Thanks for your listening!

A small boy was packing his school bag in his room, a room filled with books. Many were novels and some were short stories; many were new and some were yellowed with age; many were detective stories and some were fairy tales. Suddenly, there was a knock on the door. The small boy called Frank turned his wheelchair (轮椅) to his right and slowly opened the door. As usual it was his mom, who wanted Frank to get ready for school. Frank had his breakfast, said goodbye to his mom and started his travel to the school in his wheelchair. Frank had lost his leg when he was eight in an accident. He had to spend the rest of the life in the wheelchair. But the accident did not take away his trust in life, and he wanted to be a writer. His mother also supported his dream. Frank had not wanted to go to the school for the handicapped (残疾人). So he had joined an ordinary school.

On the way to school, he met his loving and kind-hearted friend, Lawrence. Lawrence wheeled his friend quickly and talked with him happily. He told Lawrence that there would be a story competition next week. Lawrence encouraged him to take part in it. Lawrence said, “Trust yourself. You can make it!” They reached the school in thirty minutes. Lawrence said bye to Frank and they both went to their classes.

Slowly days passed, and the Formative Exams started. They ended within a week. “Frank, the score is 100,”said the class teacher cheerfully. Frank was very happy because he had scored full marks. He wheeled his chair and again met Lawrence on the way. This time both stopped on the side and Lawrence said, “Try to take part in the story competition.” “OK, thank you, Lawrence,” said Frank excitedly. He rushed home, and wrote something on a piece of paper. His mom was very happy to see her son cheerful and excited. Actually he was going to write a short story to take part in the competition. But he didn’t know how to finish it.

Just then, his mother entered and told him that Lawrence was coming.

As all the judges (评判员) read Frank’s story, they were amazed by his brilliance (才华).