从一段给定的英文文本中，找出所有的单词并计算它们出现的频率，并按照频率从高到底输出。


"Natural language processing (NLP) is a field of computer science, artificial intelligence, and linguistics concerned with the interactions between computers and human languages."
Natural: 1
language: 1
processing: 1
(NLP): 1
is: 1
a: 1
field: 1
of: 2
computer: 1
science,: 1
artificial: 1
intelligence,: 1
and: 2
linguistics: 1
concerned: 1
with: 1
the: 2
interactions: 1
between: 1
computers: 1
human: 1
languages.: 1