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