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