Answer:
Three characteristics separated ancient Egypt from all other ancient civilizations was their ability to create beautiful, large, still standing monuments, their use of hieroglyphs.
Why ancient Egypt went into a decline?
Ancient Egypt have to face many problems as compare to past that mainly include the occupation by Assyrians then Persians and after that by Macedonians.
These problems are generally arise due to lack of control on internal processes. But the government could not get over its political problems instead of battling pride they chose to grandstand.