I can regress you can regress he can regress we can regress you can regress they can regress
V-ing form
I can be regressing you can be regressing he can be regressing we can be regressing you can be regressing they can be regressing
Perfect
I can have regressed you can have regressed he can have regressed we can have regressed you can have regressed they can have regressed
V-ing perfect
I can have been regressing you can have been regressing he can have been regressing we can have been regressing you can have been regressing they can have been regressing
Negation
Simple form
I can't regress you can't regress he can't regress we can't regress you can't regress they can't regress
V-ing form
I can't be regressing you can't be regressing he can't be regressing we can't be regressing you can't be regressing they can't be regressing
Perfect
I can't have regressed you can't have regressed he can't have regressed we can't have regressed you can't have regressed they can't have regressed
V-ing perfect
I can't have been regressing you can't have been regressing he can't have been regressing we can't have been regressing you can't have been regressing they can't have been regressing
Interrogative form
Simple form
can I regress? can you regress? can he regress? can we regress? can you regress? can they regress?
V-ing form
can I be regressing? can you be regressing? can he be regressing? can we be regressing? can you be regressing? can they be regressing?
Perfect
can I have regressed? can you have regressed? can he have regressed? can we have regressed? can you have regressed? can they have regressed?
V-ing perfect
can I have been regressing? can you have been regressing? can he have been regressing? can we have been regressing? can you have been regressing? can they have been regressing?
Interro-negative form
Simple form
can't I regress? can't you regress? can't he regress? can't we regress? can't you regress? can't they regress?
V-ing form
can't I be regressing? can't you be regressing? can't he be regressing? can't we be regressing? can't you be regressing? can't they be regressing?
Perfect
can't I have regressed? can't you have regressed? can't he have regressed? can't we have regressed? can't you have regressed? can't they have regressed?
V-ing perfect
can't I have been regressing? can't you have been regressing? can't he have been regressing? can't we have been regressing? can't you have been regressing? can't they have been regressing?