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