一般现在时:My homework is finished by me.
一般过去时:My homework was finished by me.
一般将来时:My homework will be finished by me.
现在完成时:My homework has been finished by me.
没有现在过去时只有现在进行时:My homework is being finished by me.
(其实以上的句子不用by me更好,显得更地道,但考虑到是作业……就委曲求全了)