I may crumble you may crumble he may crumble we may crumble you may crumble they may crumble
V-ing form
I may be crumbling you may be crumbling he may be crumbling we may be crumbling you may be crumbling they may be crumbling
Perfect
I may have crumbled you may have crumbled he may have crumbled we may have crumbled you may have crumbled they may have crumbled
V-ing perfect
I may have been crumbling you may have been crumbling he may have been crumbling we may have been crumbling you may have been crumbling they may have been crumbling
Negation
Simple form
I may not crumble you may not crumble he may not crumble we may not crumble you may not crumble they may not crumble
V-ing form
I may not be crumbling you may not be crumbling he may not be crumbling we may not be crumbling you may not be crumbling they may not be crumbling
Perfect
I may not have crumbled you may not have crumbled he may not have crumbled we may not have crumbled you may not have crumbled they may not have crumbled
V-ing perfect
I may not have been crumbling you may not have been crumbling he may not have been crumbling we may not have been crumbling you may not have been crumbling they may not have been crumbling
Interrogative form
Simple form
may I crumble? may you crumble? may he crumble? may we crumble? may you crumble? may they crumble?
V-ing form
may I be crumbling? may you be crumbling? may he be crumbling? may we be crumbling? may you be crumbling? may they be crumbling?
Perfect
may I have crumbled? may you have crumbled? may he have crumbled? may we have crumbled? may you have crumbled? may they have crumbled?
V-ing perfect
may I have been crumbling? may you have been crumbling? may he have been crumbling? may we have been crumbling? may you have been crumbling? may they have been crumbling?
Interro-negative form
Simple form
may I not crumble? may you not crumble? may he not crumble? may we not crumble? may you not crumble? may they not crumble?
V-ing form
may I not be crumbling? may you not be crumbling? may he not be crumbling? may we not be crumbling? may you not be crumbling? may they not be crumbling?
Perfect
may I not have crumbled? may you not have crumbled? may he not have crumbled? may we not have crumbled? may you not have crumbled? may they not have crumbled?
V-ing perfect
may I not have been crumbling? may you not have been crumbling? may he not have been crumbling? may we not have been crumbling? may you not have been crumbling? may they not have been crumbling?