Why did the writers of the us constitution allow for amendments to be added

The drafters of the US Constitution allowed for amendments to be added because they knew that times and society would change, and they knew the constitution had to be able to "adapt" to modern times without sacrificing its core elements. 

The native americans, spanish, french and americans all name places in our state. the word “arkansas” came from the quapaw indians, by way of early french explorers. at the time of the early french exploration, a tribe of indians, the quapaws, lived west of the mississippi and north of the arkansas river.