Too little light makes the eyes work harder, so they do get tired and strained.

光线不足会让用眼更费劲，双眼会感到疲劳和紧张。

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Or it may be that without the demands of work, people no longer notice even when they are tired.

或者说，没有了工作要求，大家甚至注意不到疲劳。

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Many people delay and procrastinate on their home duties because they are too tired when they get home from work.

许多人推迟、拖延家务活是因为他们做完工作回家后实在是太累了。

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Those who do, like Diego, often fall behind their classmates because they have been raised in an environment where their parents are uneducated and where the need for money now outweighs the need for education - or because after hours of work, they are simply too tired to learn.

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For those who continued to work, they reported feeling stressed and tired while doing their job.

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She also heard from a person who runs a company in Minnesota who said it was not uncommon for employees to call into the office and say they were too tired to come to work.

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