I could murder you could murder he could murder we could murder you could murder they could murder
V-ing form
I could be murdering you could be murdering he could be murdering we could be murdering you could be murdering they could be murdering
Perfect
I could have murdered you could have murdered he could have murdered we could have murdered you could have murdered they could have murdered
V-ing perfect
I could have been murdering you could have been murdering he could have been murdering we could have been murdering you could have been murdering they could have been murdering
Negation
Simple form
I could not murder you could not murder he could not murder we could not murder you could not murder they could not murder
V-ing form
I could not be murdering you could not be murdering he could not be murdering we could not be murdering you could not be murdering they could not be murdering
Perfect
I could not have murdered you could not have murdered he could not have murdered we could not have murdered you could not have murdered they could not have murdered
V-ing perfect
I could not have been murdering you could not have been murdering he could not have been murdering we could not have been murdering you could not have been murdering they could not have been murdering
Interrogative form
Simple form
could I murder? could you murder? could he murder? could we murder? could you murder? could they murder?
V-ing form
could I be murdering? could you be murdering? could he be murdering? could we be murdering? could you be murdering? could they be murdering?
Perfect
could I have murdered? could you have murdered? could he have murdered? could we have murdered? could you have murdered? could they have murdered?
V-ing perfect
could I have been murdering? could you have been murdering? could he have been murdering? could we have been murdering? could you have been murdering? could they have been murdering?
Interro-negative form
Simple form
could I not murder? could you not murder? could he not murder? could we not murder? could you not murder? could they not murder?
V-ing form
could I not be murdering? could you not be murdering? could he not be murdering? could we not be murdering? could you not be murdering? could they not be murdering?
Perfect
could I not have murdered? could you not have murdered? could he not have murdered? could we not have murdered? could you not have murdered? could they not have murdered?
V-ing perfect
could I not have been murdering? could you not have been murdering? could he not have been murdering? could we not have been murdering? could you not have been murdering? could they not have been murdering?