I could protrude you could protrude he could protrude we could protrude you could protrude they could protrude
V-ing form
I could be protruding you could be protruding he could be protruding we could be protruding you could be protruding they could be protruding
Perfect
I could have protruded you could have protruded he could have protruded we could have protruded you could have protruded they could have protruded
V-ing perfect
I could have been protruding you could have been protruding he could have been protruding we could have been protruding you could have been protruding they could have been protruding
Negation
Simple form
I could not protrude you could not protrude he could not protrude we could not protrude you could not protrude they could not protrude
V-ing form
I could not be protruding you could not be protruding he could not be protruding we could not be protruding you could not be protruding they could not be protruding
Perfect
I could not have protruded you could not have protruded he could not have protruded we could not have protruded you could not have protruded they could not have protruded
V-ing perfect
I could not have been protruding you could not have been protruding he could not have been protruding we could not have been protruding you could not have been protruding they could not have been protruding
Interrogative form
Simple form
could I protrude? could you protrude? could he protrude? could we protrude? could you protrude? could they protrude?
V-ing form
could I be protruding? could you be protruding? could he be protruding? could we be protruding? could you be protruding? could they be protruding?
Perfect
could I have protruded? could you have protruded? could he have protruded? could we have protruded? could you have protruded? could they have protruded?
V-ing perfect
could I have been protruding? could you have been protruding? could he have been protruding? could we have been protruding? could you have been protruding? could they have been protruding?
Interro-negative form
Simple form
could I not protrude? could you not protrude? could he not protrude? could we not protrude? could you not protrude? could they not protrude?
V-ing form
could I not be protruding? could you not be protruding? could he not be protruding? could we not be protruding? could you not be protruding? could they not be protruding?
Perfect
could I not have protruded? could you not have protruded? could he not have protruded? could we not have protruded? could you not have protruded? could they not have protruded?
V-ing perfect
could I not have been protruding? could you not have been protruding? could he not have been protruding? could we not have been protruding? could you not have been protruding? could they not have been protruding?