I may alter you may alter he may alter we may alter you may alter they may alter
V-ing form
I may be altering you may be altering he may be altering we may be altering you may be altering they may be altering
Perfect
I may have altered you may have altered he may have altered we may have altered you may have altered they may have altered
V-ing perfect
I may have been altering you may have been altering he may have been altering we may have been altering you may have been altering they may have been altering
Negation
Simple form
I mayn't alter you mayn't alter he mayn't alter we mayn't alter you mayn't alter they mayn't alter
V-ing form
I mayn't be altering you mayn't be altering he mayn't be altering we mayn't be altering you mayn't be altering they mayn't be altering
Perfect
I mayn't have altered you mayn't have altered he mayn't have altered we mayn't have altered you mayn't have altered they mayn't have altered
V-ing perfect
I mayn't have been altering you mayn't have been altering he mayn't have been altering we mayn't have been altering you mayn't have been altering they mayn't have been altering
Interrogative form
Simple form
may I alter? may you alter? may he alter? may we alter? may you alter? may they alter?
V-ing form
may I be altering? may you be altering? may he be altering? may we be altering? may you be altering? may they be altering?
Perfect
may I have altered? may you have altered? may he have altered? may we have altered? may you have altered? may they have altered?
V-ing perfect
may I have been altering? may you have been altering? may he have been altering? may we have been altering? may you have been altering? may they have been altering?
Interro-negative form
Simple form
mayn't I alter? mayn't you alter? mayn't he alter? mayn't we alter? mayn't you alter? mayn't they alter?
V-ing form
mayn't I be altering? mayn't you be altering? mayn't he be altering? mayn't we be altering? mayn't you be altering? mayn't they be altering?
Perfect
mayn't I have altered? mayn't you have altered? mayn't he have altered? mayn't we have altered? mayn't you have altered? mayn't they have altered?
V-ing perfect
mayn't I have been altering? mayn't you have been altering? mayn't he have been altering? mayn't we have been altering? mayn't you have been altering? mayn't they have been altering?