I can alter you can alter he can alter we can alter you can alter they can alter
Forma com V-ing
I can be altering you can be altering he can be altering we can be altering you can be altering they can be altering
Perfeito
I can have altered you can have altered he can have altered we can have altered you can have altered they can have altered
Perfeito com V-ing
I can have been altering you can have been altering he can have been altering we can have been altering you can have been altering they can have been altering
Negação
Forma simple
I can't alter you can't alter he can't alter we can't alter you can't alter they can't alter
Forma com V-ing
I can't be altering you can't be altering he can't be altering we can't be altering you can't be altering they can't be altering
Perfeito
I can't have altered you can't have altered he can't have altered we can't have altered you can't have altered they can't have altered
Perfeito com V-ing
I can't have been altering you can't have been altering he can't have been altering we can't have been altering you can't have been altering they can't have been altering
Forma interrogativa
Forma simple
can I alter? can you alter? can he alter? can we alter? can you alter? can they alter?
Forma com V-ing
can I be altering? can you be altering? can he be altering? can we be altering? can you be altering? can they be altering?
Perfeito
can I have altered? can you have altered? can he have altered? can we have altered? can you have altered? can they have altered?
Perfeito com V-ing
can I have been altering? can you have been altering? can he have been altering? can we have been altering? can you have been altering? can they have been altering?
Forma interro-Negação
Forma simple
can't I alter? can't you alter? can't he alter? can't we alter? can't you alter? can't they alter?
Forma com V-ing
can't I be altering? can't you be altering? can't he be altering? can't we be altering? can't you be altering? can't they be altering?
Perfeito
can't I have altered? can't you have altered? can't he have altered? can't we have altered? can't you have altered? can't they have altered?
Perfeito com V-ing
can't I have been altering? can't you have been altering? can't he have been altering? can't we have been altering? can't you have been altering? can't they have been altering?