English verb conjugation
MAY UNDERPIN

Regular verb: underpin - underpinned - underpinned

Affirmation

Simple form	V-ing form
I may underpin you may underpin he may underpin we may underpin you may underpin they may underpin	I may be underpinning you may be underpinning he may be underpinning we may be underpinning you may be underpinning they may be underpinning
Perfect	V-ing perfect
I may have underpinned you may have underpinned he may have underpinned we may have underpinned you may have underpinned they may have underpinned	I may have been underpinning you may have been underpinning he may have been underpinning we may have been underpinning you may have been underpinning they may have been underpinning

Negation

Simple form	V-ing form
I mayn't underpin you mayn't underpin he mayn't underpin we mayn't underpin you mayn't underpin they mayn't underpin	I mayn't be underpinning you mayn't be underpinning he mayn't be underpinning we mayn't be underpinning you mayn't be underpinning they mayn't be underpinning
Perfect	V-ing perfect
I mayn't have underpinned you mayn't have underpinned he mayn't have underpinned we mayn't have underpinned you mayn't have underpinned they mayn't have underpinned	I mayn't have been underpinning you mayn't have been underpinning he mayn't have been underpinning we mayn't have been underpinning you mayn't have been underpinning they mayn't have been underpinning

Interrogative form

Simple form	V-ing form
may I underpin? may you underpin? may he underpin? may we underpin? may you underpin? may they underpin?	may I be underpinning? may you be underpinning? may he be underpinning? may we be underpinning? may you be underpinning? may they be underpinning?
Perfect	V-ing perfect
may I have underpinned? may you have underpinned? may he have underpinned? may we have underpinned? may you have underpinned? may they have underpinned?	may I have been underpinning? may you have been underpinning? may he have been underpinning? may we have been underpinning? may you have been underpinning? may they have been underpinning?

Interro-negative form

Simple form	V-ing form
mayn't I underpin? mayn't you underpin? mayn't he underpin? mayn't we underpin? mayn't you underpin? mayn't they underpin?	mayn't I be underpinning? mayn't you be underpinning? mayn't he be underpinning? mayn't we be underpinning? mayn't you be underpinning? mayn't they be underpinning?
Perfect	V-ing perfect
mayn't I have underpinned? mayn't you have underpinned? mayn't he have underpinned? mayn't we have underpinned? mayn't you have underpinned? mayn't they have underpinned?	mayn't I have been underpinning? mayn't you have been underpinning? mayn't he have been underpinning? mayn't we have been underpinning? mayn't you have been underpinning? mayn't they have been underpinning?