题目内容
It is difficult to cross the desert by car, but not a impossible.
―Could I hand in my composition after class?
―Of course, you _____.
A．might B．will C．can D．should
upset A. cubic B. trust C. altitude D. unique
America hopes to start building a base that can contribute to exist all the time on the moon within 20 years. By the mid-2020s, astronauts will be staying there for six months a time. So what do scientists think food and water will be like for those first moon residents?
In the short term, food would have to be brought from Earth. The dream, however, is to grow things in greenhouses on the moon. “You’d grow things in liquid---there’s no reason why that wouldn’t work,” says Pillinger, a professor. This would mean floating plants in a nutrient-rich solution of water. “Soil is not a necessary thing for plants; it’s only to keep them standing upright,” Pillinger adds.
It would take at least a decade of experiments after the base was built before such a plan would work, however. The main problem is working out how to get nutrients from the lunar(月球的) soil. “Getting all that to work requires a minimum level of infrastructure(基础设施）present before you can start experimenting with greenhouses,” says Pillinger.
Finding strong plants to grow in space will also be hard, though scientists are already working on it: scientist Amy Grunden of North Carolina State University has been working on genetically engineering food crops that can be grown in hars, off- planet environment.
Water is a somewhat easier prospect(前景). One of the reasons that America wants to put its base at the moon’s south pole is that it thinks that, in the permanently shaded craters, there are large pools of frozen water. If that is true, it could easily be mined and used to drink and to create oxygen for the habitants.
41. The passage is mainly about______.
A. life on the moon by 2020
B. America’s first moon base that exists forever
C. food and water on the future moon base
D. housing for settlers on the future moon base
42. How do people plant on the moon in the future?
A. By burying plants in the lunar soil
B. By growing plants in water.
C. By keeping plants standing straight.
D. By making use of the moonlight
43. What difficulty will scientists meet in solving the food problem?
A. How to find water to irrigate plants.
B. Where to experiment with plants.
A. How to grow plants in the moon soil.
D. What plants are suitable to grow in the moon
44. Scientists want to build the base on the moon’s south pole because_______.
A. there is oxygen for people to breathe
B. people have found the frozen water that can be drunk there
C. it is a place where water will possibly be found and supplied
D. there are large pools that can let people have a swim.
He admits that he has a __________(偏见) against women drivers
---How did you know about it?
---I heard it ____ the radio.
A. in B. at C. on D. for
Among them I like this kind of food ______, for it is ______ sugar and water.
A. best, mostly B. best, most C. most, best D. most, mostly
F____________, a kind and brave peasant passed there and saved the wounded soldier.
