I may sift you may sift she may sift we may sift you may sift they may sift
V-ing form
I may be sifting you may be sifting she may be sifting we may be sifting you may be sifting they may be sifting
Perfect
I may have sifted you may have sifted she 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 she 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 she 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 she 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 she 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 she 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 she sift? may we sift? may you sift? may they sift?
V-ing form
may I be sifting? may you be sifting? may she be sifting? may we be sifting? may you be sifting? may they be sifting?
Perfect
may I have sifted? may you have sifted? may she 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 she 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 she 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 she 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 she 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 she have been sifting? mayn't we have been sifting? mayn't you have been sifting? mayn't they have been sifting?