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