-Talk to your school International Student Office about your plan and then, file I-539 to change F-1 to H-4. You need to make sure your spouse's H-1 status is valid before you file I-539. Because after your spouse lost prvious job, his H-1 status is invalid and thus, the H-1 transfer may be approved without I-94. If so, you can not change F-1 to H-4 unless your spouse gets the H-1 visa to reenter US.
非常感谢