I could avalanche you could avalanche he could avalanche we could avalanche you could avalanche they could avalanche
V-ing form
I could be avalanching you could be avalanching he could be avalanching we could be avalanching you could be avalanching they could be avalanching
Perfect
I could have avalanched you could have avalanched he could have avalanched we could have avalanched you could have avalanched they could have avalanched
V-ing perfect
I could have been avalanching you could have been avalanching he could have been avalanching we could have been avalanching you could have been avalanching they could have been avalanching
Negation
Simple form
I could not avalanche you could not avalanche he could not avalanche we could not avalanche you could not avalanche they could not avalanche
V-ing form
I could not be avalanching you could not be avalanching he could not be avalanching we could not be avalanching you could not be avalanching they could not be avalanching
Perfect
I could not have avalanched you could not have avalanched he could not have avalanched we could not have avalanched you could not have avalanched they could not have avalanched
V-ing perfect
I could not have been avalanching you could not have been avalanching he could not have been avalanching we could not have been avalanching you could not have been avalanching they could not have been avalanching
Interrogative form
Simple form
could I avalanche? could you avalanche? could he avalanche? could we avalanche? could you avalanche? could they avalanche?
V-ing form
could I be avalanching? could you be avalanching? could he be avalanching? could we be avalanching? could you be avalanching? could they be avalanching?
Perfect
could I have avalanched? could you have avalanched? could he have avalanched? could we have avalanched? could you have avalanched? could they have avalanched?
V-ing perfect
could I have been avalanching? could you have been avalanching? could he have been avalanching? could we have been avalanching? could you have been avalanching? could they have been avalanching?
Interro-negative form
Simple form
could I not avalanche? could you not avalanche? could he not avalanche? could we not avalanche? could you not avalanche? could they not avalanche?
V-ing form
could I not be avalanching? could you not be avalanching? could he not be avalanching? could we not be avalanching? could you not be avalanching? could they not be avalanching?
Perfect
could I not have avalanched? could you not have avalanched? could he not have avalanched? could we not have avalanched? could you not have avalanched? could they not have avalanched?
V-ing perfect
could I not have been avalanching? could you not have been avalanching? could he not have been avalanching? could we not have been avalanching? could you not have been avalanching? could they not have been avalanching?