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