陈述句变为一般疑问句，

楼主你好 你这样改 是不对的

应该是这样的：

(1)We usually do our homework after school．

____Do you usually do your homework after school?

(2)Helen often does her housework after office．

_____Does Helen often do her housework after office?

助动词是用来提问的，不存在什么省略的问题，后面的do和does都是有实际作用的谓语动词，是“做，完成”的意思。

I walk to the shop.
Do you walk to the shop?

这个是对的

不对 因为在这两个句子里do does都是实意动词"用".而把DO DOES提前之后,这两个词是助动词,无实意.这两个句子应该这样变:
Do we usually do our homework after school．

Does Helen often do her housework after office．

Do you usually do your homework after school?

Does helen often do her housework after office?

当然不对了,后面的DO是动词

记住，一变二，三不管，这都是人称哦！！好好学习吧！！