I may sightsee you may sightsee she may sightsee we may sightsee you may sightsee they may sightsee
V-ing form
I may be sightseeing you may be sightseeing she may be sightseeing we may be sightseeing you may be sightseeing they may be sightseeing
Perfect
I may have sightseed you may have sightseed she may have sightseed we may have sightseed you may have sightseed they may have sightseed
V-ing perfect
I may have been sightseeing you may have been sightseeing she may have been sightseeing we may have been sightseeing you may have been sightseeing they may have been sightseeing
Negation
Simple form
I mayn't sightsee you mayn't sightsee she mayn't sightsee we mayn't sightsee you mayn't sightsee they mayn't sightsee
V-ing form
I mayn't be sightseeing you mayn't be sightseeing she mayn't be sightseeing we mayn't be sightseeing you mayn't be sightseeing they mayn't be sightseeing
Perfect
I mayn't have sightseed you mayn't have sightseed she mayn't have sightseed we mayn't have sightseed you mayn't have sightseed they mayn't have sightseed
V-ing perfect
I mayn't have been sightseeing you mayn't have been sightseeing she mayn't have been sightseeing we mayn't have been sightseeing you mayn't have been sightseeing they mayn't have been sightseeing
Interrogative form
Simple form
may I sightsee? may you sightsee? may she sightsee? may we sightsee? may you sightsee? may they sightsee?
V-ing form
may I be sightseeing? may you be sightseeing? may she be sightseeing? may we be sightseeing? may you be sightseeing? may they be sightseeing?
Perfect
may I have sightseed? may you have sightseed? may she have sightseed? may we have sightseed? may you have sightseed? may they have sightseed?
V-ing perfect
may I have been sightseeing? may you have been sightseeing? may she have been sightseeing? may we have been sightseeing? may you have been sightseeing? may they have been sightseeing?
Interro-negative form
Simple form
mayn't I sightsee? mayn't you sightsee? mayn't she sightsee? mayn't we sightsee? mayn't you sightsee? mayn't they sightsee?
V-ing form
mayn't I be sightseeing? mayn't you be sightseeing? mayn't she be sightseeing? mayn't we be sightseeing? mayn't you be sightseeing? mayn't they be sightseeing?
Perfect
mayn't I have sightseed? mayn't you have sightseed? mayn't she have sightseed? mayn't we have sightseed? mayn't you have sightseed? mayn't they have sightseed?
V-ing perfect
mayn't I have been sightseeing? mayn't you have been sightseeing? mayn't she have been sightseeing? mayn't we have been sightseeing? mayn't you have been sightseeing? mayn't they have been sightseeing?