I could quarrel you could quarrel he could quarrel we could quarrel you could quarrel they could quarrel
V-ing form
I could be quarrelling you could be quarrelling he could be quarrelling we could be quarrelling you could be quarrelling they could be quarrelling
Perfect
I could have quarrelled you could have quarrelled he could have quarrelled we could have quarrelled you could have quarrelled they could have quarrelled
V-ing perfect
I could have been quarrelling you could have been quarrelling he could have been quarrelling we could have been quarrelling you could have been quarrelling they could have been quarrelling
Negation
Simple form
I could not quarrel you could not quarrel he could not quarrel we could not quarrel you could not quarrel they could not quarrel
V-ing form
I could not be quarrelling you could not be quarrelling he could not be quarrelling we could not be quarrelling you could not be quarrelling they could not be quarrelling
Perfect
I could not have quarrelled you could not have quarrelled he could not have quarrelled we could not have quarrelled you could not have quarrelled they could not have quarrelled
V-ing perfect
I could not have been quarrelling you could not have been quarrelling he could not have been quarrelling we could not have been quarrelling you could not have been quarrelling they could not have been quarrelling
Interrogative form
Simple form
could I quarrel? could you quarrel? could he quarrel? could we quarrel? could you quarrel? could they quarrel?
V-ing form
could I be quarrelling? could you be quarrelling? could he be quarrelling? could we be quarrelling? could you be quarrelling? could they be quarrelling?
Perfect
could I have quarrelled? could you have quarrelled? could he have quarrelled? could we have quarrelled? could you have quarrelled? could they have quarrelled?
V-ing perfect
could I have been quarrelling? could you have been quarrelling? could he have been quarrelling? could we have been quarrelling? could you have been quarrelling? could they have been quarrelling?
Interro-negative form
Simple form
could I not quarrel? could you not quarrel? could he not quarrel? could we not quarrel? could you not quarrel? could they not quarrel?
V-ing form
could I not be quarrelling? could you not be quarrelling? could he not be quarrelling? could we not be quarrelling? could you not be quarrelling? could they not be quarrelling?
Perfect
could I not have quarrelled? could you not have quarrelled? could he not have quarrelled? could we not have quarrelled? could you not have quarrelled? could they not have quarrelled?
V-ing perfect
could I not have been quarrelling? could you not have been quarrelling? could he not have been quarrelling? could we not have been quarrelling? could you not have been quarrelling? could they not have been quarrelling?