1 . Plants and exposure to greenery have been found to have mental health benefits and like any new skill or hobby, taking care of houseplants comes with difficulty. Anyone starting to care for plants should be patient and allow themselves time to learn the basics. Here are several plants recommended for giving mental health benefits:
Snake Plant
These popular indoor plants have a striking appearance, with dark green sword-shaped leaves that have yellow or white stripes. It is a great first plant, and is very easy to care for. It grows in spaces with low sunlight, has visual appeal and cleans the air.
Lavender
Well known for its relaxing smell, lavender has a calming effect, aids in reducing stress, promotes sleep and specially has anti-inflammatory (抗炎的) effects when used as a medicine for skin. You can cut it off and dry the leaves or even put them into your bath.
Pothos
If you want to go bright green, try pothos. The plants grow long stems that can hang from a pot and grow downward, or the stems can climb and grow upward. They clean the air and look beautiful hanging down a bookcase or shelf.
Lemon Balm
This fragrant green herb is part of the mint family and is simple to plant. Known for its calming properties, it has a light lemony smell and has been used to improve sleep, reduce stress and anxiety.
Basil
The experience of growing, picking and using herbs you’ve grown yourself has a positive impact on your mental health, creating a sense of accomplishment. Eating basil has health benefits too. It has properties that help to relieve stress and anxiety, and eating it can clear your mind.
1. What do snake plant and pothos have in common?| A．Long stems. | B．Bright green leaves. |
| C．Purifying the air. | D．Relaxing your mind. |
| A．Promoting sleep. | B．Resisting inflammation. |
| C．Reducing stress. | D．Clearing your mind. |
| A．Basil. | B．Snake Plants. | C．Pothos. | D．Lavender. |
2 . Trees are able to defend themselves against diseases. They have both protective structures and protective processes. Thanks in large part to research done by Dr. Alex Shigo, we now know a great deal more about the way trees protect themselves than we did 50 years ago.
Just as our skin keeps harmful bacteria on the outside, bark (树皮) keeps out tree diseases. Since they can’t move around to avoid dangers, trees need thicker “skin” than we do. Living and non-living tissues protect tree trunks, roots, and branches from mechanical injury, drying out, and diseases.
But when something destroys this first line of defense — tears through the bark — what happens internally is interesting. When an injury occurs, a tree will transform some of its stored sugars to make masses of defensive chemicals, which are then distributed in a specific pattern internally around the wound. Dr. Shigo was the first to document this pattern, which he called CODIT — Compartmentalization (分室化) of Decay (腐烂) in Trees.
In making these CODIT compartments, trees form chemical walls to protect themselves from infection. The success of this walling-off process depends a lot on the species. Hard maple, for instance, can generate a strong CODIT response while species like soft maple achieve only an average level. Some, on the other hand, barely manage to form any chemical walls.
Overall tree vitality is another important factor. Even a hard maple may not be able to form strong chemical walls if it’s in a weak state. By definition, landscape trees are stressed as compared to their forest-living cousins. A street tree is worse off, faced with limited root space, air pollution, and more. The size of the injury also makes a difference. Even a healthy tree can have its defenses destroyed by a large wound.
Humans can help maximize trees’ defense capability by watering during dry seasons, keeping things out of the root zone, etc. In return, trees will help keep us in good health by offering shade, beauty, and companionship.
1. What will happen first if diseases come close to trees?| A．Infection will occur internally. | B．Bark will provide protection |
| C．Chemical walls will take effect. | D．Defense chemicals will be formed. |
| A．Groundbreaking. | B．Conservative. | C．Ambiguous. | D．Straightforward. |
| A．Trees can form chemical walls |
| B．The size of the injury affects CODIT. |
| C．Trees cannot protect themselves if weakened. |
| D．The effectiveness of CODIT varies among species. |
| A．The gift of the trees. | B．The magic of CODIT. |
| C．The function of the bark. | D．The self-preservation of the trees. |
3 . Bananas and apples continue to ripen after being picked. Cherries and grapes do not. The difference between climacteric (后熟的) and non-climacteric fruits matters to fruit growers and greengrocers, who must ensures their products are in excellent condition when arriving at the marketplace. But how those differences originally came about remains unclear.
In a paper in Biology Letters, Fukano Yuya and Tachiki Yuuya of the University of Tokyo offer a suggestion. Fruits, they observe, exist to solve a problem faced by all plants - how best to spread their progeny around. Wrapping their seeds in a sugary flesh, to provide a tasty meal, serves as a way to got animals to do this for them. They do, however, need to ensure their fruits favour the animals most likely to do the distributing. They propose that climacterism or non-climacterism is a way to achieve this. If ground-living animals are the main distributors, then the continuing ripening of fallen fruit is beneficial. If, by contrast, those distributors are tree-living or flying animals, which can feed on unfallen fruit, then non-climacteric fruits will do well.
To test their idea, the two researchers combed through 276 papers about 80 sorts of fruits. They discovered 35 of these fruits were eaten by both groups of animals. But of those where one group or the other were the dominant consumers, 15 of the 19 eaten mainly by ground-living animals were climacteric.
Their assumption is strengthened by other evidence. They point out non-climacteric fruits tend to have vivid colors which may help them stand out amid the leaves, advertising their presence. Climacteric fruits are generally better hidden, making them harder to spot until they have fallen to the ground.
1. What did the two researchers try to find out through their study?| A．What enables fruits to stay in perfect condition. |
| B．How some fruits stand out in the trees, but others fail. |
| C．How many animals play the role of distributors for fruits. |
| D．Why some fruits stop ripening when picked, and others don't. |
| A．Later generations. | B．Hidden qualities. |
| C．Fresh fragrance. | D．Unknown disease. |
| A．Bananas definitely fall into the category. |
| B．They may appeal to flying birds. |
| C．They tend to remain hidden among leaves. |
| D．Ground-living animals generally feed on them. |
| A．The Condition of Products: What Greengrocers Care. |
| B．The Reproduction of Plants: Depending on Themselves. |
| C．The Evolution of Fruit: Finding the Right Distributors. |
| D．The Choice of Animals: Looking for bright-colored fruits. |
