[简答题]can grow in poor soil

[填空题]With the forests cut down, soil can easily lose its fertility when the essential nutrients are ______.

[单项选择]Why did nothing grow in the big garden
A. The soil was spoiled.
B. The soil was sandy.
C. It was saline-alkali land.
D. The soil was not fertilized.

[填空题]The balance of nature can prevent soil deterioration.

[填空题]grow

[填空题]·can grow in places of hard conditions

[单项选择]

Scientists have created a tomato that can grow on salty water. The plant is the first crop of its kind ever produced in the world.
Its significance can not be overestimated (高估). The new technology can help mankind solve the problem of feeding its ever-expanding population. It is estimated that by 2025 the world population will amount to more than 9 billion, an increase of 3 billion over 2000. Each day 240,000 more people are born, ready to be fed like the rest of us. Unfortunately, not all the land on Earth can be used to grow crops for humans. About 24.7 million acres of the problem is irrigation (灌溉). When farmers water their crops, salts in the water also enter the soil. Over time, salts such as sodium (钠) and calcium (钙) build up to such a point that they severely harm the growth of crops. Salts destroy most plants’ ability to draw up water through their roots.
But, the new variety of tomato produced by American and Canadian scientists can store salts i
A. importance
B. quality
C. price
D. quantity

[简答题]How can science be encouraged to flourish and grow How can the results of science be used to the best purpose for the benefit of humanity 71. It was to find the answers to these question% which are not merely academic but practical ones, that this whole inquiry into the place of science in society was undertaken. It can be justified only in so far as it helps to find them.
The way to answer the first question is to find the best conditions, external and internal, which have in the past helped the progress of science and to anticipate the changed needs of the present and future. The answer to the second question, which depends on the first, is set out towards the end of this chapter. Some of the external conditions for the flourishing of science in the past have already been discussed. 72. In essence they are provided only in periods of social and economic advance, when science is given social importance and material means and is continually stimulated to new activity by