I may umber you may umber he may umber we may umber you may umber they may umber
V-ing form
I may be umbering you may be umbering he may be umbering we may be umbering you may be umbering they may be umbering
Perfect
I may have umbered you may have umbered he may have umbered we may have umbered you may have umbered they may have umbered
V-ing perfect
I may have been umbering you may have been umbering he may have been umbering we may have been umbering you may have been umbering they may have been umbering
Negation
Simple form
I may not umber you may not umber he may not umber we may not umber you may not umber they may not umber
V-ing form
I may not be umbering you may not be umbering he may not be umbering we may not be umbering you may not be umbering they may not be umbering
Perfect
I may not have umbered you may not have umbered he may not have umbered we may not have umbered you may not have umbered they may not have umbered
V-ing perfect
I may not have been umbering you may not have been umbering he may not have been umbering we may not have been umbering you may not have been umbering they may not have been umbering
Interrogative form
Simple form
may I umber? may you umber? may he umber? may we umber? may you umber? may they umber?
V-ing form
may I be umbering? may you be umbering? may he be umbering? may we be umbering? may you be umbering? may they be umbering?
Perfect
may I have umbered? may you have umbered? may he have umbered? may we have umbered? may you have umbered? may they have umbered?
V-ing perfect
may I have been umbering? may you have been umbering? may he have been umbering? may we have been umbering? may you have been umbering? may they have been umbering?
Interro-negative form
Simple form
may I not umber? may you not umber? may he not umber? may we not umber? may you not umber? may they not umber?
V-ing form
may I not be umbering? may you not be umbering? may he not be umbering? may we not be umbering? may you not be umbering? may they not be umbering?
Perfect
may I not have umbered? may you not have umbered? may he not have umbered? may we not have umbered? may you not have umbered? may they not have umbered?
V-ing perfect
may I not have been umbering? may you not have been umbering? may he not have been umbering? may we not have been umbering? may you not have been umbering? may they not have been umbering?