I could define you could define she could define we could define you could define they could define
V-ing form
I could be defining you could be defining she could be defining we could be defining you could be defining they could be defining
Perfect
I could have defined you could have defined she could have defined we could have defined you could have defined they could have defined
V-ing perfect
I could have been defining you could have been defining she could have been defining we could have been defining you could have been defining they could have been defining
Negation
Simple form
I could not define you could not define she could not define we could not define you could not define they could not define
V-ing form
I could not be defining you could not be defining she could not be defining we could not be defining you could not be defining they could not be defining
Perfect
I could not have defined you could not have defined she could not have defined we could not have defined you could not have defined they could not have defined
V-ing perfect
I could not have been defining you could not have been defining she could not have been defining we could not have been defining you could not have been defining they could not have been defining
Interrogative form
Simple form
could I define? could you define? could she define? could we define? could you define? could they define?
V-ing form
could I be defining? could you be defining? could she be defining? could we be defining? could you be defining? could they be defining?
Perfect
could I have defined? could you have defined? could she have defined? could we have defined? could you have defined? could they have defined?
V-ing perfect
could I have been defining? could you have been defining? could she have been defining? could we have been defining? could you have been defining? could they have been defining?
Interro-negative form
Simple form
could I not define? could you not define? could she not define? could we not define? could you not define? could they not define?
V-ing form
could I not be defining? could you not be defining? could she not be defining? could we not be defining? could you not be defining? could they not be defining?
Perfect
could I not have defined? could you not have defined? could she not have defined? could we not have defined? could you not have defined? could they not have defined?
V-ing perfect
could I not have been defining? could you not have been defining? could she not have been defining? could we not have been defining? could you not have been defining? could they not have been defining?