The World Is Getting Smaller
Imagine this: a television screen the size and thickness of a piece of paper. You carry it around in your pocket and take it out when you want to watch a show. Imagine a guitar so tiny you can’t see it with the human eye, but you can hear sounds when its strings are plucked（拨）. Some people say the future is big, but when it comes to technology, the world is getting smaller.
Nanotechnology（纳米技术）is the science that deals with doing things in a very small way, and it is being explored and developed all over the globe. Micromachines too small to be seen by the human eye are being designed to do many things that larger machines do today. And these machines, no longer in diameter（直径）than a human hair, are extremely powerful. Many scientists say nanotechnology will produce the next industrial revolution.
Maybe the area where nanotechnology will have the biggest impact is medical science. Imagine nanobots in medicine. Thousands or even millions of tiny machines can be sent into the human body with specific missions. For example, they can be designed to find and destroy cancer cells or viruses. Other machines may stay in the human body permanently to help organs that are not functioning properly.
Think of the possibilities in using such tiny machines in surgery. Imagine machines so small you can swallow them in a pill or inject them into your bloodstream through a needle. After you’ve had too many years of junk food, these tiny robots could be sent into your arteries（动脉）to clean them. An intelligent machine in your heart would look around to find the problem and then repair it. If you needed an operation, it would be almost like swallowing the surgeon.
When could all of this happen? Scientists predict that much of this is possible in the next 30 years. After all, when your grandparents were young, they would have laughed if someone told them a person could walk on the moon. Thousands of scientists around the world are working on these micromachines. Nanotechnology is just around the corner.
1. Paragraph 2 mainly discusses ________.
A. nanotechnology B. human eye C. large machines D. human hair
2. According to the passage, the tiny medical instruments ________.
A. can stay in human body and cure the diseases
B. are too small to be repaired
C. may not function well in human body
D. can also be used to send human onto the moon
3. The phrase “just around the corner” in the last sentence means “________”.
A. in the distance B. right under your notice
C. likely to happen soon D. beyond all imagination