4.py，将一段英文文本中连续重复了2次的英文单词改为1个。 flower, the characteristic reproductive structure of angiosperms. As popularly used, the term “flower” especially applies when part or all of the reproductive structure is distinctive in colour and form.

以下是代码实现：

import re

text = "flower, the characteristic reproductive structure of angiosperms. As popularly used, the term “flower” especially applies when part or all of the reproductive structure is distinctive in colour and form."

# 利用正则表达式找到连续重复了2次的英文单词
pattern = r'\b(\w+)\b\s+\b\1\b'
repeated_words = re.findall(pattern, text)

# 将重复的单词替换为单个单词
for word in repeated_words:
    text = re.sub(r'\b' + word + r'\b\s+\b' + word + r'\b', word, text)

print(text)

输出结果为：

flower, the characteristic reproductive structure of angiosperms. As popularly used, the term “flower” especially applies when part or all of the reproductive structure is distinctive in colour and form.

由于输入的文本中没有连续重复2次的英文单词，所以输出结果与原文本相同。如果输入的文本中有连续重复2次的英文单词，则会将其改为1个单词。