This feedback system is used by the eye in an effort to attain an ideal eye length, neither farsighted nor nearsighted. This state is called emmetropia.

眼睛尽力用这个反馈系统，达到理想的视力长度，不是远视也不是近视，这个状态就称正常视力。

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Opacity of the eye lens can be induced by deficiency of certain vitamins.

眼球晶状体的混浊可由缺乏某些维生素引起。

《柯林斯英汉双解大词典》

His captaincy of the team was ended by mild eye trouble.

他的队长生涯因轻微眼疾而结束。

《柯林斯英汉双解大词典》

But the man and woman do not believe in the evil eye, that a person can harm you by looking at you.

VOA: special.2009.09.06

The Andromeda Galaxy is big enough and near enough to be seen by the unaided eye in the star group Andromeda on a dark night.

VOA: special.2009.01.20

The latest 3-D TVs work by dividing picture images in two,one for each eye.

VOA: special.2010.01.26

Her range of vision seemed obscured by the eye patch and I doubt that she even saw me, although my adolescent heart wished otherwise.

NPR: The Sounds of Love: Valentine's Day Music

The CATT (Comparison of Age-Related Macular Degeneration Treatments Trials) study, slated for release next week, is sponsored by the National Eye Institute, part of the federal National Institutes of Health.

FORBES: Patient Safety and 'Off-Label' Drug Use

By understanding the eye scans a website, web graphic designers can optimize their site thus to their visitors.

FORBES: Fee Alert: Verizon Tacks On $2 For Phone And Online Bill Pay