Why don't you ask ________ to help you?

someone
这里虽是问句,但请求某人帮助时比较明确的,在对象明确时即使是问句一样用someone
再如
would you like some juice?那如果是Why didn't you buy ______ for yourself?该是something还是anything呢？这里选 anything，解释差不多，这里是问句，且对象不明确，要买什么不知道。