I may doubt you may doubt he may doubt we may doubt you may doubt they may doubt
V-ing form
I may be doubting you may be doubting he may be doubting we may be doubting you may be doubting they may be doubting
Perfect
I may have doubted you may have doubted he may have doubted we may have doubted you may have doubted they may have doubted
V-ing perfect
I may have been doubting you may have been doubting he may have been doubting we may have been doubting you may have been doubting they may have been doubting
Negation
Simple form
I may not doubt you may not doubt he may not doubt we may not doubt you may not doubt they may not doubt
V-ing form
I may not be doubting you may not be doubting he may not be doubting we may not be doubting you may not be doubting they may not be doubting
Perfect
I may not have doubted you may not have doubted he may not have doubted we may not have doubted you may not have doubted they may not have doubted
V-ing perfect
I may not have been doubting you may not have been doubting he may not have been doubting we may not have been doubting you may not have been doubting they may not have been doubting
Interrogative form
Simple form
may I doubt? may you doubt? may he doubt? may we doubt? may you doubt? may they doubt?
V-ing form
may I be doubting? may you be doubting? may he be doubting? may we be doubting? may you be doubting? may they be doubting?
Perfect
may I have doubted? may you have doubted? may he have doubted? may we have doubted? may you have doubted? may they have doubted?
V-ing perfect
may I have been doubting? may you have been doubting? may he have been doubting? may we have been doubting? may you have been doubting? may they have been doubting?
Interro-negative form
Simple form
may I not doubt? may you not doubt? may he not doubt? may we not doubt? may you not doubt? may they not doubt?
V-ing form
may I not be doubting? may you not be doubting? may he not be doubting? may we not be doubting? may you not be doubting? may they not be doubting?
Perfect
may I not have doubted? may you not have doubted? may he not have doubted? may we not have doubted? may you not have doubted? may they not have doubted?
V-ing perfect
may I not have been doubting? may you not have been doubting? may he not have been doubting? may we not have been doubting? may you not have been doubting? may they not have been doubting?