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