【推荐1】On a summer day in 1961, Yuan Longping, the celebrated agronomist (农学家) whose death was widely mourned across China, was inspecting a test field in Hunan province, when he came across a single rice plant bearing 230 grains.     1     and Yuan thought he may have found a naturally high-yield strain of rice.

Yuan collected its grains and planted them the following year, hoping to find a way to boost rice yields in the nation. To his disappointment, the resulting plants demonstrated a variety of useful traits (特性),     2    . With a background in genetic engineering, Yuan concluded that the parent must have been a hybrid.

“If natural hybrid rice had such a strong advantage, then artificially created hybrid rice should also have an advantage,” he wrote in an article. At that time, it was widely believed that rice could not be hybridized. Rice is a self-pollinating (自花传粉) crop,     3    .

To develop hybrid rice, it was necessary to find a sterile male plant and then use it to crossbreed with other varieties.     4    , Yuan decided in 1964 to seriously study the possibilities.

The first breakthrough came in 1970, and after painstaking research and testing, the team successfully developed a hybrid-rice strain in 1973 and it was used in large scale cultivation.

    5     — where about 20 percent of the world’s population lives on less than 9 percent of the world’s arable land — and beyond.

【推荐3】It was realized that if an apparatus (装置) could be designed to send out radio waves all the time and record the echoes from any approaching airplanes, it would be a wonderful method of defense in the last war.

Scientists set about solving the problem and radar was invented. An apparatus was made which sent out waves in pulses, and the presence of a distant airplane was shown on the screen (this is what we have in a television set). In this way radar station could detect the approach of enemy aircraft.

After the war radar was put to peaceful uses. It is now installed at airports to guide airplanes down safely in fog. It is fitted to ships so that they are warned of obstructions (障碍物) ahead, such as icebergs. It guides ships into port. It provided airplanes and ships with a magic eye, with which they can see far into the distance, in the dark or in fog.

【推荐2】Scientists have made a “breakthrough” in handling nuclear fusion (聚变). The US Department of Energy officially announced the milestone in fusion energy research.

For the first time, researchers created a nuclear fusion reaction that produced more energy than they put into the process. The experiment, conducted at Lawrence Livermore National Laboratory in California, generated 3.15 megajoules of energy, more than the 2.05 megajoules put into creating it.

Nuclear fusion works by forcing together two atoms-most often hydrogen-to make a heavier one-like helium (氦). This explosive process releases massive amounts of energy, the Department of Energy explains. Fusion is the opposite of fission (裂变), the reaction that powers nuclear reactors used commercially today.

Fusion occurs naturally in the heart of the Sun and the stars, providing these cosmic (宇宙的) objects with fuel. Since the 1950s, scientists have been trying to reproduce it on Earth in order to make use of the so-called clean, cheap, and almost limitless electricity. According to the International Atomic Energy Agency, fusion generates four times more energy per kilogram than the fission used to power nuclear plants, and nearly 4 million times more energy than burning oil or coal. What’s more, unlike fossil fuels, fusion doesn’t release carbon dioxide the greenhouse gas that’s the main driver of climate change-into the atmosphere. And unlike nuclear fission, fusion doesn’t create long-lived radioactive waste, according to the Department of Energy. But so far, nuclear fusion hasn’t solved our energy problems on a grand scale.

The recent announcement is a huge step forward in nuclear fusion energy, but applying the technology at commercial scale is likely still years away. Chanda Prescod Weinstein, a theoretical physicist, pointed out that the process the Department of Energy uses requires tritium (氚), a rare and radioactive isotope (同位素)of hydrogen. “It may yet convey important information that is ultimately transformative. We don’t know yet,” Prescod Weinstein tweeted. Investors, including Amazon founder Jeff Bezos, have poured billions into clean energy field trying to make fusion commercially workable, and the recent announcement is likely to continue that trend.

【推荐3】Agriculture has come a long way from its ancient beginnings. Long ago, farmers would work hard on their individual plots of land, using simple tools or even their bare hands. They tended to their crops for many hours each day so that the crops grew well.     1     For example, a single storm could destroy a whole year’s work, while a summer of good weather could ensure a good harvest.

Modern science and technology have helped to greatly reduce the back-breaking labour involved in farming, along with the reliance on luck and guesswork.     2    

Probably one of the most beneficial innovations is drip irrigation, which has made it possible to develop big, green farms in the middle of the desert. Simcha Blass, an Israeli scientist, discovered this new way of irrigation in the 1930s. Through this discovery, farmers can now produce crops on dry land without needing much water.     3     The limited and focused use of just the right amount of water also denies moisture (水分) to weeds, keeping them from harming the crops.

    4     However, what if an area has plenty of water, but little usable soil? As it turns out, it is possible to grow plants without using soil at all. With hydroponics (水培), plant roots are supported by rocks or a fiber mat. Nutrient-rich water is then provided so that the plants can grow. Recent research has centered on vertical hydroponics farming. With a vertical farm, the crops are planted in containers that are piled into plant skyscrapers.     5    

With such technological advances, the image of a farmer pushing a plough will eventually become a thing of the past.

【推荐1】Critical thinking is the ability to think clearly and rationally, understanding the logical connection between ideas. Critical thinking has been the subject of much debate and thought since the time of early Greek philosophers such as Plato and Socrates and has continued to be a subject of discussion into the modern age, for example the ability to recognise fake news.

Critical thinking might be described as the ability to engage in reflective and independent thinking. In nature, critical thinking requires you to use your ability to reason. It is about being an active learner rather than a passive recipient of information.

Critical thinkers rigorously (严厉地) question ideas and assumptions rather than accepting them at face value. They will always seek to determine whether the ideas, arguments and findings represent the entire picture and are open to finding that they do not.

One of the most important aspects of critical thinking is to decide what you are aiming to achieve and then make a decision based on a range of possibilities.

Once you have clarified that aim for yourself you should use it as the starting point in all future situations requiring thought and, possibly, further decision making. Where needed, make your workmates, family or those around you aware of your intention to pursue this goal. You must then discipline yourself to keep on track until changing circumstances mean you have to revisit the start of the decision-making process.

However, there are things that get in the way of simple decision making. We all carry with us a range of likes and dislikes, learnt behaviours and personal preferences developed throughout our lives; they are the hallmarks of being human. A major contribution to ensuring we think critically is to be aware of these personal characteristics, preferences and biases (偏见) and make allowance for them when considering possible next steps.

The more clearly, we are aware of ourselves, our strengths and weaknesses, the more likely our critical thinking will be productive.