将字符串中的每个第一个字符转换为大写

def capitalize_first_letter(string):
    words = string.split()  # 将字符串分割为单词列表
    capitalized_words = [word.capitalize() for word in words]  # 将每个单词的第一个字符转换为大写
    capitalized_string = ' '.join(capitalized_words)  # 将单词列表合并为字符串
    return capitalized_string

# 示例用法
input_string = "hello world! how are you?"
output_string = capitalize_first_letter(input_string)
print(output_string)