I could sandwich you could sandwich he could sandwich we could sandwich you could sandwich they could sandwich
V-ing form
I could be sandwiching you could be sandwiching he could be sandwiching we could be sandwiching you could be sandwiching they could be sandwiching
Perfect
I could have sandwiched you could have sandwiched he could have sandwiched we could have sandwiched you could have sandwiched they could have sandwiched
V-ing perfect
I could have been sandwiching you could have been sandwiching he could have been sandwiching we could have been sandwiching you could have been sandwiching they could have been sandwiching
Negation
Simple form
I could not sandwich you could not sandwich he could not sandwich we could not sandwich you could not sandwich they could not sandwich
V-ing form
I could not be sandwiching you could not be sandwiching he could not be sandwiching we could not be sandwiching you could not be sandwiching they could not be sandwiching
Perfect
I could not have sandwiched you could not have sandwiched he could not have sandwiched we could not have sandwiched you could not have sandwiched they could not have sandwiched
V-ing perfect
I could not have been sandwiching you could not have been sandwiching he could not have been sandwiching we could not have been sandwiching you could not have been sandwiching they could not have been sandwiching
Interrogative form
Simple form
could I sandwich? could you sandwich? could he sandwich? could we sandwich? could you sandwich? could they sandwich?
V-ing form
could I be sandwiching? could you be sandwiching? could he be sandwiching? could we be sandwiching? could you be sandwiching? could they be sandwiching?
Perfect
could I have sandwiched? could you have sandwiched? could he have sandwiched? could we have sandwiched? could you have sandwiched? could they have sandwiched?
V-ing perfect
could I have been sandwiching? could you have been sandwiching? could he have been sandwiching? could we have been sandwiching? could you have been sandwiching? could they have been sandwiching?
Interro-negative form
Simple form
could I not sandwich? could you not sandwich? could he not sandwich? could we not sandwich? could you not sandwich? could they not sandwich?
V-ing form
could I not be sandwiching? could you not be sandwiching? could he not be sandwiching? could we not be sandwiching? could you not be sandwiching? could they not be sandwiching?
Perfect
could I not have sandwiched? could you not have sandwiched? could he not have sandwiched? could we not have sandwiched? could you not have sandwiched? could they not have sandwiched?
V-ing perfect
could I not have been sandwiching? could you not have been sandwiching? could he not have been sandwiching? could we not have been sandwiching? could you not have been sandwiching? could they not have been sandwiching?