I can regret you can regret she can regret we can regret you can regret they can regret
V-ing form
I can be regreting you can be regreting she can be regreting we can be regreting you can be regreting they can be regreting
Perfect
I can have regreted you can have regreted she can have regreted we can have regreted you can have regreted they can have regreted
V-ing perfect
I can have been regreting you can have been regreting she can have been regreting we can have been regreting you can have been regreting they can have been regreting
Negation
Simple form
I can't regret you can't regret she can't regret we can't regret you can't regret they can't regret
V-ing form
I can't be regreting you can't be regreting she can't be regreting we can't be regreting you can't be regreting they can't be regreting
Perfect
I can't have regreted you can't have regreted she can't have regreted we can't have regreted you can't have regreted they can't have regreted
V-ing perfect
I can't have been regreting you can't have been regreting she can't have been regreting we can't have been regreting you can't have been regreting they can't have been regreting
Interrogative form
Simple form
can I regret? can you regret? can she regret? can we regret? can you regret? can they regret?
V-ing form
can I be regreting? can you be regreting? can she be regreting? can we be regreting? can you be regreting? can they be regreting?
Perfect
can I have regreted? can you have regreted? can she have regreted? can we have regreted? can you have regreted? can they have regreted?
V-ing perfect
can I have been regreting? can you have been regreting? can she have been regreting? can we have been regreting? can you have been regreting? can they have been regreting?
Interro-negative form
Simple form
can't I regret? can't you regret? can't she regret? can't we regret? can't you regret? can't they regret?
V-ing form
can't I be regreting? can't you be regreting? can't she be regreting? can't we be regreting? can't you be regreting? can't they be regreting?
Perfect
can't I have regreted? can't you have regreted? can't she have regreted? can't we have regreted? can't you have regreted? can't they have regreted?
V-ing perfect
can't I have been regreting? can't you have been regreting? can't she have been regreting? can't we have been regreting? can't you have been regreting? can't they have been regreting?