找到字符串的第n个单词/元素并替换它

def replace_nth_word(string, n, new_word):
    words = string.split()  # 按空格拆分字符串得到单词列表
    if len(words) < n:
        return "找不到第{}个单词/元素".format(n)
    else:
        words[n-1] = new_word  # 替换第n个单词/元素
        return ' '.join(words)  # 拼接替换后的单词列表为字符串

# 示例用法
string = "Hello world, how are you?"
n = 2  # 替换第2个单词
new_word = "everyone"
result = replace_nth_word(string, n, new_word)
print(result)