I could auction you could auction he could auction we could auction you could auction they could auction
V-ing form
I could be auctioning you could be auctioning he could be auctioning we could be auctioning you could be auctioning they could be auctioning
Perfect
I could have auctioned you could have auctioned he could have auctioned we could have auctioned you could have auctioned they could have auctioned
V-ing perfect
I could have been auctioning you could have been auctioning he could have been auctioning we could have been auctioning you could have been auctioning they could have been auctioning
Negation
Simple form
I couldn't auction you couldn't auction he couldn't auction we couldn't auction you couldn't auction they couldn't auction
V-ing form
I couldn't be auctioning you couldn't be auctioning he couldn't be auctioning we couldn't be auctioning you couldn't be auctioning they couldn't be auctioning
Perfect
I couldn't have auctioned you couldn't have auctioned he couldn't have auctioned we couldn't have auctioned you couldn't have auctioned they couldn't have auctioned
V-ing perfect
I couldn't have been auctioning you couldn't have been auctioning he couldn't have been auctioning we couldn't have been auctioning you couldn't have been auctioning they couldn't have been auctioning
Interrogative form
Simple form
could I auction? could you auction? could he auction? could we auction? could you auction? could they auction?
V-ing form
could I be auctioning? could you be auctioning? could he be auctioning? could we be auctioning? could you be auctioning? could they be auctioning?
Perfect
could I have auctioned? could you have auctioned? could he have auctioned? could we have auctioned? could you have auctioned? could they have auctioned?
V-ing perfect
could I have been auctioning? could you have been auctioning? could he have been auctioning? could we have been auctioning? could you have been auctioning? could they have been auctioning?
Interro-negative form
Simple form
couldn't I auction? couldn't you auction? couldn't he auction? couldn't we auction? couldn't you auction? couldn't they auction?
V-ing form
couldn't I be auctioning? couldn't you be auctioning? couldn't he be auctioning? couldn't we be auctioning? couldn't you be auctioning? couldn't they be auctioning?
Perfect
couldn't I have auctioned? couldn't you have auctioned? couldn't he have auctioned? couldn't we have auctioned? couldn't you have auctioned? couldn't they have auctioned?
V-ing perfect
couldn't I have been auctioning? couldn't you have been auctioning? couldn't he have been auctioning? couldn't we have been auctioning? couldn't you have been auctioning? couldn't they have been auctioning?