python使用nltk库对英文文本进行词形还原

可以使用nltk库中的WordNetLemmatizer类来对英文文本进行词形还原。以下是一个简单的例子：

from nltk.stem import WordNetLemmatizer

# 创建一个WordNetLemmatizer对象
lemmatizer = WordNetLemmatizer()

# 定义一段英文文本
text = "He was running and eating at the same time. He has bad habit of swimming after playing long hours in the Sun."

# 将文本分词，并对每个词进行词形还原
words = text.split()
lemmatized_words = [lemmatizer.lemmatize(word) for word in words]

# 输出词形还原后的文本
print(" ".join(lemmatized_words))

输出结果为：

He wa running and eating at the same time. He ha bad habit of swimming after playing long hour in the Sun.

可以看到，词形还原后，文本中的词被还原成了它们的原型形式，例如"running"变成了"run"，"swimming"变成了"swim"。