Some experts feel that the automobile is to “die”. They see a day in the not?too?distant future when all autos will be abandoned and allowed to become rotten iron and steel rubbish. __1.__ They think that the car will remain a leading means of urban travel in the near future.

_2._ It should become smaller, safer, and more money?saving, and should not be powered by the petrol engine. The car of the future should be far more pollution?free than present types.

Regardless of its power source, the auto in the future will still be the main problem in urban traffic jam. _3._

When the auto enters the freeway system, a retractable arm, which can be moved inwards or backwards, will drop from the auto and touch a rail that is similar to the subway trains electrically powered from the system, and control of the vehicle will pass to a central computer. 4._

The driver will use a telephone to dial instructions about his destination into the system. The computer will calculate the best route, and reserve space for the car all the way to the correct exit from the freeway. _5._ It is guessed that an automated freeway will be able to handle 10,000 vehicles per hour, compared with the 1,500 to 2,000 vehicles that can be carried by a present?day freeway.

AOther authorities, however, think the auto is here to stay.

BThe computer will then monitor all of the car's movements.

COne proposed solution to this problem is the automated freeway system.

DExperts have different views on what role autos will play in the near future.

EThe motorcar will undoubtedly change significantly over the next 30 years.

FDrivers in the freeway system can sit back and do nothing but control the direction.

GThe driver will then be free to relax and wait for the sound speaker that will warn him of his coming exit.

1______ 2.______ 3.______ 4.______ 5.______

 

Do you have trouble getting started in the morning? Do you have problems learning early in the day? If you do, you are not alone, _1.__ They learn better at night than they do in the morning.

To investigate when cockroaches(蟑螂) learn best, researchers at Vanderbill University tested the insects for which odor(peppermint 薄荷 or vanilla 香草) they preferred. Most cockroaches preferred the smell of vanilla to that of peppermint at all times. __2.__ Therefore, the scientists trained the cockroaches to prefer the peppermint smell by rewarding the insects with a taste of sugar water when they approached a peppermint smell. _3.__

When the cockroaches were trained at night, they remembered the new associations(peppermintsugar water; vanillasalt water) for up to 48 hours. However, if the cockroaches were trained in the morning, they quickly forgot which smell went with which water. __4._

So, cockroaches learn better at night than they do in the morning. _5._ Because of this, it is likely that information they gather at night will be more useful to them. These experiments provide some clues about the interactions between body rhythms, learning and memory.

AWhen these insects moved toward a vanilla smell, on the other hand, they were punished with a taste of salt.

BThis result thus shows that the time when they were trained decided the effect of their learning.

CThey are often more active and tend to search for food during the night.

DThey were also found to like sugar water, but not salt water.

ECockroaches have the same problem!

FBut they prefer warm conditions found within buildings.

GPest species adapt easily to their environment.

 

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