my mother usually does the housework at weekends改成

问题补充：

my mother usually does the housework at weekends改成过去式

答案：

does为do的第三人称单数形式,do的过去式为did,改成过去式就是My mother usually did the housework at weekends.

另,housework前应该是不加定冠词the的,不知道是不是我搞错了.

一点拙见,希望可以帮到你.