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