I can falter you can falter he can falter we can falter you can falter they can falter
V-ing form
I can be faltering you can be faltering he can be faltering we can be faltering you can be faltering they can be faltering
Perfect
I can have faltered you can have faltered he can have faltered we can have faltered you can have faltered they can have faltered
V-ing perfect
I can have been faltering you can have been faltering he can have been faltering we can have been faltering you can have been faltering they can have been faltering
Negation
Simple form
I can't falter you can't falter he can't falter we can't falter you can't falter they can't falter
V-ing form
I can't be faltering you can't be faltering he can't be faltering we can't be faltering you can't be faltering they can't be faltering
Perfect
I can't have faltered you can't have faltered he can't have faltered we can't have faltered you can't have faltered they can't have faltered
V-ing perfect
I can't have been faltering you can't have been faltering he can't have been faltering we can't have been faltering you can't have been faltering they can't have been faltering
Interrogative form
Simple form
can I falter? can you falter? can he falter? can we falter? can you falter? can they falter?
V-ing form
can I be faltering? can you be faltering? can he be faltering? can we be faltering? can you be faltering? can they be faltering?
Perfect
can I have faltered? can you have faltered? can he have faltered? can we have faltered? can you have faltered? can they have faltered?
V-ing perfect
can I have been faltering? can you have been faltering? can he have been faltering? can we have been faltering? can you have been faltering? can they have been faltering?
Interro-negative form
Simple form
can't I falter? can't you falter? can't he falter? can't we falter? can't you falter? can't they falter?
V-ing form
can't I be faltering? can't you be faltering? can't he be faltering? can't we be faltering? can't you be faltering? can't they be faltering?
Perfect
can't I have faltered? can't you have faltered? can't he have faltered? can't we have faltered? can't you have faltered? can't they have faltered?
V-ing perfect
can't I have been faltering? can't you have been faltering? can't he have been faltering? can't we have been faltering? can't you have been faltering? can't they have been faltering?