如何使结果成为一个恰当的句子？

Question

我制作了一个非常简单的程序，请求输入，并在最后加上逗号或问号。如果句子以“为什么”、“如何”等开头，程序会添加一个问号

但是我怎样才能把最后一个逗号变成句点，这样我才能造出一个恰当的句子呢

守则：

def sentence_maker(phrase):
    x = ("Why", "What", "Who", "How")
    sentence = phrase.capitalize()
    if sentence.startswith(x):
        return "{}?\n".format(sentence)
    else:
        return "{},".format(sentence)

results = []
while True:
    y = input("Say something: ")
    if y=="end":
        break
    else:
        results.append(sentence_maker(y))

print(" " .join(results))

这样做的目的是使其工作如下： 输入： say something: hello say something: how are you say something: i'am good say something: thank you

输出：

 Hello, How are you?
I'am good, Thank you.

Answer 1

解决此问题的一种方法是在注册输入为“end”后编辑最后一个元素

while True:
    y = input("Say something: ")
    if y=="end":
        results[-1] = results[-1][:-1] + "."
        break
    else:
        results.append(sentence_maker(y))

测试输出：

Say something: Why
Say something: the
Say something: quick
Say something: brown
Say something: fox
Say something: jumps
Say something: end
Why?
 The, Quick, Brown, Fox, Jumps.