近视是指一个人对近距离的物体比较容易看清而远处的物体看不清楚的现象，它的产生是由于光线的聚焦点落在了视网膜之前。
When you are short-sighted, your eyes focus well only on close objects, while more distant objects appear blurred. This is because light rays focus in front of the retina.
猪流感病毒被认为通过猪之间的近距离接触进行传播，另一种可能的传播方式是携带病毒的物体将病毒从被感染的猪群传播到健康的猪群中。
Swine flu viruses are thought to be spread mostly through close contact among pigs and possibly from contaminated objects moving between infected and uninfected pigs.
为此我们需要将光分解为数个波的形式，目前还不清楚当光源靠近物体时，光子是否能分解并形成新的波，如果使用光线技术，光子在近距离破坏，物体无法实现隐形。
If we use ray optic techniques where light travels in beams - photons break down at close range and the object does not appear invisible.
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