【推荐1】Our abilities grow stronger as we age

It’s believed that people reach their mental peak in their 20s. However, this isn’t completely true. According to a recent study by scientists from the Massachusetts Institute of Technology in the US, people are best at doing different things at different ages. They studied many people aged 10 to 90 years old, who were asked to take part in different memory tests.

【推荐2】Toothpaste (牙膏) does more than just keep our teeth bright and white. It can be used wisely in many other ways. Here are some useful tips that can save us time and money, and leave a fresh smell — using toothpaste!

A hungry fly speeds through a forest. It smells nectar and lands on a green leaf. Many plants produce nectar, a liquid that insects feed on. The fly starts to drink the sweet liquid. Suddenly, the fly’s world turns green. The two sides of the leaf close against each other. Long green teeth lock together around it. The fly has been caught by a Venus flytrap. There is no chance to run away.

The Venus flytrap is perhaps the most famous killer plant, a kind of meat-eating plant. It grows in very few places, such as wetlands near the coast of North Carolina in America. The Venus flytrap is not a large plant. It grows to be only about a foot tall. The plant has white flowers in the spring, but it is the plant’s leaves that make it so interesting. The ends of the leaves have folding parts with stiff, tiny hairs. These are the plant’s “traps”. What does the Venus flytrap eat? It doesn’t only eat flies. As you might guess, the Venus flytrap also eats spiders, ants, and crickets. The Venus flytrap makes most of its food with sun, air, and water, just like other plants. Living things just give it more nutrition to grow well in wetlands.

How does this plant trap and eat living things? The Venus flytrap uses-a sweet liquid-nectar, to attract its food. When a fly lands on one of the plant’s open traps, hairs on the surface make the trap closed. As soon as the trap closes, the fly is dinner! However, scientists have only recently started to understand how it hunts and eats. After years of study, plant scientist Alexander Volkov believes he now knows the Venus flytrap’s mystery. “This,” says Volkov, “is an electrical plant.”

There are three small hairs along each of the Venus flytrap’s two leaves. When an insect touches a hair, it creates an electrical signal in the leaf. The insect can keep feeding-for now. But if it touches another hair within 20 seconds, the trap shuts immediately. This system allows the plant to tell the difference between a drop of water, for example, and a moving creature.

Once trapped, an insect has little chance of survival. Instead of nectar, the Venus fly trap now releases a different liquid-one that slowly eats away at the insect. Ten days later, hardly anything is left. The plant’s leaves open again, and the Venus flytrap is ready for its next meal.

【推荐3】①Do you know podcasts (播客)? Have you ever paid for educational podcasts or live videos? Ask some people and most of them will say yes. “Pay-for-knowledge” has been a fashionable thing these years. Everything you think of can be found online, skills of talking, designing, computer programming and so on.

②Why is “Pay-for-knowledge” industry (产业) developing so quickly? First, its development is based on (基于) the Internet. With a fast network and a smart phone, anyone who has passed the identity (身份) check can be an online teacher, and anyone with an online account (账户) can buy “Pay-for-knowledge” products that he or she wants at a good price. Second, people are afraid to miss any information. They hope for more useful information which is usually at the hands of experts. Moreover, the need to learn new skills in today’s job market also pushes people to learn on such educational podcasts.

③The industry of “Pay-for-knowledge” has proved to be a great way of making money. It promises possibilities of turning information into money. It is good for the development of our country and it can help sellers make lots of money. Besides, buyers can enjoy self-growth from it. What’s more, this is a reflection (反映) of people’s respect for knowledge and talents.

④However, “Pay-for-knowledge” also causes a few problems. For one thing, the market is full of eye-catching words such as “How to be a good CEO?” which sound like if you pay for it, you are sure to succeed. For another, a large number of customers buy them just for showing off. That means, with or without these products, they can make it anyway, because they are those who have the ability to learn by themselves.

⑤In general, the best is the one that suits you most. “Pay-for-knowledge” may be used as a good start for self-growth. But be careful when you make a choice, or your dream of success may not come true.

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