I may climb you may climb he may climb we may climb you may climb they may climb
V-ing form
I may be climbing you may be climbing he may be climbing we may be climbing you may be climbing they may be climbing
Perfect
I may have climbed you may have climbed he may have climbed we may have climbed you may have climbed they may have climbed
V-ing perfect
I may have been climbing you may have been climbing he may have been climbing we may have been climbing you may have been climbing they may have been climbing
Negation
Simple form
I may not climb you may not climb he may not climb we may not climb you may not climb they may not climb
V-ing form
I may not be climbing you may not be climbing he may not be climbing we may not be climbing you may not be climbing they may not be climbing
Perfect
I may not have climbed you may not have climbed he may not have climbed we may not have climbed you may not have climbed they may not have climbed
V-ing perfect
I may not have been climbing you may not have been climbing he may not have been climbing we may not have been climbing you may not have been climbing they may not have been climbing
Interrogative form
Simple form
may I climb? may you climb? may he climb? may we climb? may you climb? may they climb?
V-ing form
may I be climbing? may you be climbing? may he be climbing? may we be climbing? may you be climbing? may they be climbing?
Perfect
may I have climbed? may you have climbed? may he have climbed? may we have climbed? may you have climbed? may they have climbed?
V-ing perfect
may I have been climbing? may you have been climbing? may he have been climbing? may we have been climbing? may you have been climbing? may they have been climbing?
Interro-negative form
Simple form
may I not climb? may you not climb? may he not climb? may we not climb? may you not climb? may they not climb?
V-ing form
may I not be climbing? may you not be climbing? may he not be climbing? may we not be climbing? may you not be climbing? may they not be climbing?
Perfect
may I not have climbed? may you not have climbed? may he not have climbed? may we not have climbed? may you not have climbed? may they not have climbed?
V-ing perfect
may I not have been climbing? may you not have been climbing? may he not have been climbing? may we not have been climbing? may you not have been climbing? may they not have been climbing?