听力文摘：吃蔬菜的正确时间

When a vegetable is growing, it protects itself from insects by producing chemical nutrients¹ thatmake it taste bad or seem repellant to predators².

蔬菜在生长的过程中会产生化学养分，使其口感变差或让捕食者排斥，以此来保护自己免受虫害。

Some of these nutrients—in particularphytochemicals—have been shown to fight cancer in people.

这其中的一些化学养分，特别是植物素，已经被证明可以用于人类抵抗癌症。

What's more, many vegetables areable to anticipate when insects will attack, and will ramp³ up its defenses accordingly.

并且，许多蔬菜都能够提前预见昆虫的进攻，并相应地增加自身防御力。

Even after vegetables are harvested and they're no longer fighting insects, these garden wonderscan still be made to produce more nutrients at certain times.

即便蔬菜已经丰收，无需再抵抗昆虫，这些菜园中的奇迹依旧能在某些时候产生较多的营养素。

This is done by varying a vegetable'slight exposure to simulate the experience of night turning into day.

方法就是通过改变蔬菜的光照量来制造出昼夜交替的效果。

Studies have shown thatvegetables stored this way produce more phytochemicals during the light cycle.

研究表明这种方式下储存的蔬菜会在光照周期中产生更多的植物素。

So eating vegetables during this golden period means you're getting more nutritional⁴ value!Exactly.

所以在这段黄金时间吃蔬菜意味着你能获得更多的营养价值！

It's not yet clear how people might be able to activate⁵ these nutrition-packed properties at home.

至于人们如何能在家就激活这些储存的营养素，还不甚清楚。

Perhaps simply storing veggies in the dark and then subjecting them to a flash of light is enoughto trigger the process.

也许只是简单地将蔬菜储存在暗处再给予它们一闪光亮就足以触发这一过程。

Or it could be more complex.

或者还会更复杂。

In any case, more research could help us findways to eating vegetables' even more helpful.

无论如何，更多的研究会帮助我们找到使蔬菜营养价值最大化的方法。

1 nutrients   

n.（食品或化学品）营养物，营养品( nutrient的名词复数 )

参考例句：

• a lack of essential nutrients 基本营养的缺乏
• Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》

2 predators   

n.食肉动物( predator的名词复数 )；奴役他人者（尤指在财务或性关系方面）

参考例句：

• birds and their earthbound predators 鸟和地面上捕食它们的动物
• The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》

3 ramp   

n.暴怒，斜坡，坡道；vi.作恐吓姿势，暴怒，加速；vt.加速

参考例句：

• That driver drove the car up the ramp.那司机将车开上了斜坡。
• The factory don't have that capacity to ramp up.这家工厂没有能力加速生产。

4 nutritional   

adj.营养的，滋养的

参考例句：

• A diet lacking in nutritional value will not keep a person healthy.缺乏营养价值的饮食不能维持人的健康。
• The labels on food products give a lot of information about their nutritional content.食品上的标签提供很多关于营养成分的信息。

5 activate   

vt.使活动起来，使开始起作用

参考例句：

• We must activate the youth to study.我们要激励青年去学习。
• These push buttons can activate the elevator.这些按钮能启动电梯。