شرکت در آزمون آنلاین زبان انگلیسی 2 - زبان انگلیسی 2 | آزمون شماره 7024

Could you please get ......... white bread from the store?

One destructive environmental effect of roads is that they take part in the … of plant species from one area to another which creates problems for plants already growing in that area.

If you keep on walking down this street, you will see a red … pointing to the left.

Passage (1)

A device has been developed that enables babies born blind to see the world through echoes from an ultrasonic scanner. Dr. Tom Bower, of Edinburgh University psychology department, told the British Association annual conference that he gave the device to a 16-week-old boy in the U.S., and the child responded to it within half a minute of putting it on.

  The battery-operated scanner sends out a pulse of ultra-sound through a cone attached to the forehead. Through earplugs the baby is able to hear echoes in stereo which tell him what lies in front. By moving his head, he will detect sounds from different parts of the room.

  The closer the object is, the lower the pitch of the sound is. The bigger it is, the louder the sound is.    The child can also establish whether the object is hard or soft: a hard object will give a clear sound, and a soft one will give a fuzzy sound with overtones. Normal voice commands can be heard by the baby while he is wearing the device.

  Bower first tried it out on a blind baby from the Berkeley children’s hospital in California. The baby, Denis Daughters, seemed delighted and played hide-and-seek with his mother after a few days. He enjoyed finding her in a room. At the age of nine months, he had reached the development stage of a normal sighted baby. He was able to perform tests such as balancing an object on two prongs or on a table edge. This may sound unimportant, but few sighted children can perform such a task before this age.

What is the best title for the passage?