Why does the Constitution and the Declaration of Independence are called Living documents?

Question

I need an answer why to write my government report.

The Constitution is a living document because we can amend and change it. Also, the Supreme Court continuously interprets the Constitution in light of modern problems.

im sorry i cant understand that well.
can u explain it more in depth?

These Web sites go into more depth about why the Constitution is a living document.

http://capitolhillcoffeehouse.com/chch_news_037.htm

http://bensguide.gpo.gov/6-8/documents/constitution/about.html

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