这实际上是在nltk.org的主页上：
>>> import nltk>>> sentence = """At eight o'clock on Thursday morning... Arthur didn't feel very good.""">>> tokens = nltk.word_tokenize(sentence)>>> tokens['At', 'eight', "o'clock", 'on', 'Thursday', 'morning','Arthur', 'did', "n't", 'feel', 'very', 'good', '.']
