I can abstain you can abstain she can abstain we can abstain you can abstain they can abstain
V-ing form
I can be abstaining you can be abstaining she can be abstaining we can be abstaining you can be abstaining they can be abstaining
Perfect
I can have abstained you can have abstained she can have abstained we can have abstained you can have abstained they can have abstained
V-ing perfect
I can have been abstaining you can have been abstaining she can have been abstaining we can have been abstaining you can have been abstaining they can have been abstaining
Negation
Simple form
I cannot abstain you cannot abstain she cannot abstain we cannot abstain you cannot abstain they cannot abstain
V-ing form
I cannot be abstaining you cannot be abstaining she cannot be abstaining we cannot be abstaining you cannot be abstaining they cannot be abstaining
Perfect
I cannot have abstained you cannot have abstained she cannot have abstained we cannot have abstained you cannot have abstained they cannot have abstained
V-ing perfect
I cannot have been abstaining you cannot have been abstaining she cannot have been abstaining we cannot have been abstaining you cannot have been abstaining they cannot have been abstaining
Interrogative form
Simple form
can I abstain? can you abstain? can she abstain? can we abstain? can you abstain? can they abstain?
V-ing form
can I be abstaining? can you be abstaining? can she be abstaining? can we be abstaining? can you be abstaining? can they be abstaining?
Perfect
can I have abstained? can you have abstained? can she have abstained? can we have abstained? can you have abstained? can they have abstained?
V-ing perfect
can I have been abstaining? can you have been abstaining? can she have been abstaining? can we have been abstaining? can you have been abstaining? can they have been abstaining?
Interro-negative form
Simple form
can I not abstain? can you not abstain? can she not abstain? can we not abstain? can you not abstain? can they not abstain?
V-ing form
can I not be abstaining? can you not be abstaining? can she not be abstaining? can we not be abstaining? can you not be abstaining? can they not be abstaining?
Perfect
can I not have abstained? can you not have abstained? can she not have abstained? can we not have abstained? can you not have abstained? can they not have abstained?
V-ing perfect
can I not have been abstaining? can you not have been abstaining? can she not have been abstaining? can we not have been abstaining? can you not have been abstaining? can they not have been abstaining?