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