I can backflip you can backflip he can backflip we can backflip you can backflip they can backflip
V-ing form
I can be backfliping you can be backfliping he can be backfliping we can be backfliping you can be backfliping they can be backfliping
Perfect
I can have backfliped you can have backfliped he can have backfliped we can have backfliped you can have backfliped they can have backfliped
V-ing perfect
I can have been backfliping you can have been backfliping he can have been backfliping we can have been backfliping you can have been backfliping they can have been backfliping
Negation
Simple form
I can't backflip you can't backflip he can't backflip we can't backflip you can't backflip they can't backflip
V-ing form
I can't be backfliping you can't be backfliping he can't be backfliping we can't be backfliping you can't be backfliping they can't be backfliping
Perfect
I can't have backfliped you can't have backfliped he can't have backfliped we can't have backfliped you can't have backfliped they can't have backfliped
V-ing perfect
I can't have been backfliping you can't have been backfliping he can't have been backfliping we can't have been backfliping you can't have been backfliping they can't have been backfliping
Interrogative form
Simple form
can I backflip? can you backflip? can he backflip? can we backflip? can you backflip? can they backflip?
V-ing form
can I be backfliping? can you be backfliping? can he be backfliping? can we be backfliping? can you be backfliping? can they be backfliping?
Perfect
can I have backfliped? can you have backfliped? can he have backfliped? can we have backfliped? can you have backfliped? can they have backfliped?
V-ing perfect
can I have been backfliping? can you have been backfliping? can he have been backfliping? can we have been backfliping? can you have been backfliping? can they have been backfliping?
Interro-negative form
Simple form
can't I backflip? can't you backflip? can't he backflip? can't we backflip? can't you backflip? can't they backflip?
V-ing form
can't I be backfliping? can't you be backfliping? can't he be backfliping? can't we be backfliping? can't you be backfliping? can't they be backfliping?
Perfect
can't I have backfliped? can't you have backfliped? can't he have backfliped? can't we have backfliped? can't you have backfliped? can't they have backfliped?
V-ing perfect
can't I have been backfliping? can't you have been backfliping? can't he have been backfliping? can't we have been backfliping? can't you have been backfliping? can't they have been backfliping?