如何使用NLTK重写一个句子或段落

import nltk

nltk.download('punkt')

from nltk.tokenize import sent_tokenize

text = "这是一个示例句子。这是另一个示例句子。"
sentences = sent_tokenize(text)

from nltk.tokenize import word_tokenize

words = []
for sentence in sentences:
    words.extend(word_tokenize(sentence))

from nltk import pos_tag
from nltk.corpus import wordnet

# 对单词进行词性标注
tagged_words = pos_tag(words)

# 重写动词
for i, (word, tag) in enumerate(tagged_words):
    if tag.startswith('VB'):
        # 获取动词的原形
        lemma = wordnet.morphy(word, wordnet.VERB)
        if lemma is not None:
            tagged_words[i] = (lemma, tag)

# 重建句子
rewritten_sentence = ' '.join([word for word, _ in tagged_words])