I may stumble you may stumble she may stumble we may stumble you may stumble they may stumble
V-ing form
I may be stumbling you may be stumbling she may be stumbling we may be stumbling you may be stumbling they may be stumbling
Perfect
I may have stumbled you may have stumbled she may have stumbled we may have stumbled you may have stumbled they may have stumbled
V-ing perfect
I may have been stumbling you may have been stumbling she may have been stumbling we may have been stumbling you may have been stumbling they may have been stumbling
Negation
Simple form
I mayn't stumble you mayn't stumble she mayn't stumble we mayn't stumble you mayn't stumble they mayn't stumble
V-ing form
I mayn't be stumbling you mayn't be stumbling she mayn't be stumbling we mayn't be stumbling you mayn't be stumbling they mayn't be stumbling
Perfect
I mayn't have stumbled you mayn't have stumbled she mayn't have stumbled we mayn't have stumbled you mayn't have stumbled they mayn't have stumbled
V-ing perfect
I mayn't have been stumbling you mayn't have been stumbling she mayn't have been stumbling we mayn't have been stumbling you mayn't have been stumbling they mayn't have been stumbling
Interrogative form
Simple form
may I stumble? may you stumble? may she stumble? may we stumble? may you stumble? may they stumble?
V-ing form
may I be stumbling? may you be stumbling? may she be stumbling? may we be stumbling? may you be stumbling? may they be stumbling?
Perfect
may I have stumbled? may you have stumbled? may she have stumbled? may we have stumbled? may you have stumbled? may they have stumbled?
V-ing perfect
may I have been stumbling? may you have been stumbling? may she have been stumbling? may we have been stumbling? may you have been stumbling? may they have been stumbling?
Interro-negative form
Simple form
mayn't I stumble? mayn't you stumble? mayn't she stumble? mayn't we stumble? mayn't you stumble? mayn't they stumble?
V-ing form
mayn't I be stumbling? mayn't you be stumbling? mayn't she be stumbling? mayn't we be stumbling? mayn't you be stumbling? mayn't they be stumbling?
Perfect
mayn't I have stumbled? mayn't you have stumbled? mayn't she have stumbled? mayn't we have stumbled? mayn't you have stumbled? mayn't they have stumbled?
V-ing perfect
mayn't I have been stumbling? mayn't you have been stumbling? mayn't she have been stumbling? mayn't we have been stumbling? mayn't you have been stumbling? mayn't they have been stumbling?