English verb conjugation
COULD OVERTURN

Regular verb: overturn - overturned - overturned

Affirmation

Simple form	V-ing form
I could overturn you could overturn he could overturn we could overturn you could overturn they could overturn	I could be overturning you could be overturning he could be overturning we could be overturning you could be overturning they could be overturning
Perfect	V-ing perfect
I could have overturned you could have overturned he could have overturned we could have overturned you could have overturned they could have overturned	I could have been overturning you could have been overturning he could have been overturning we could have been overturning you could have been overturning they could have been overturning

Negation

Simple form	V-ing form
I could not overturn you could not overturn he could not overturn we could not overturn you could not overturn they could not overturn	I could not be overturning you could not be overturning he could not be overturning we could not be overturning you could not be overturning they could not be overturning
Perfect	V-ing perfect
I could not have overturned you could not have overturned he could not have overturned we could not have overturned you could not have overturned they could not have overturned	I could not have been overturning you could not have been overturning he could not have been overturning we could not have been overturning you could not have been overturning they could not have been overturning

Interrogative form

Simple form	V-ing form
could I overturn? could you overturn? could he overturn? could we overturn? could you overturn? could they overturn?	could I be overturning? could you be overturning? could he be overturning? could we be overturning? could you be overturning? could they be overturning?
Perfect	V-ing perfect
could I have overturned? could you have overturned? could he have overturned? could we have overturned? could you have overturned? could they have overturned?	could I have been overturning? could you have been overturning? could he have been overturning? could we have been overturning? could you have been overturning? could they have been overturning?

Interro-negative form

Simple form	V-ing form
could I not overturn? could you not overturn? could he not overturn? could we not overturn? could you not overturn? could they not overturn?	could I not be overturning? could you not be overturning? could he not be overturning? could we not be overturning? could you not be overturning? could they not be overturning?
Perfect	V-ing perfect
could I not have overturned? could you not have overturned? could he not have overturned? could we not have overturned? could you not have overturned? could they not have overturned?	could I not have been overturning? could you not have been overturning? could he not have been overturning? could we not have been overturning? could you not have been overturning? could they not have been overturning?