English verb conjugation
CAN RETAIN

Regular verb: retain - retained - retained

Affirmation

Simple form	V-ing form
I can retain you can retain she can retain we can retain you can retain they can retain	I can be retaining you can be retaining she can be retaining we can be retaining you can be retaining they can be retaining
Perfect	V-ing perfect
I can have retained you can have retained she can have retained we can have retained you can have retained they can have retained	I can have been retaining you can have been retaining she can have been retaining we can have been retaining you can have been retaining they can have been retaining

Negation

Simple form	V-ing form
I cannot retain you cannot retain she cannot retain we cannot retain you cannot retain they cannot retain	I cannot be retaining you cannot be retaining she cannot be retaining we cannot be retaining you cannot be retaining they cannot be retaining
Perfect	V-ing perfect
I cannot have retained you cannot have retained she cannot have retained we cannot have retained you cannot have retained they cannot have retained	I cannot have been retaining you cannot have been retaining she cannot have been retaining we cannot have been retaining you cannot have been retaining they cannot have been retaining

Interrogative form

Simple form	V-ing form
can I retain? can you retain? can she retain? can we retain? can you retain? can they retain?	can I be retaining? can you be retaining? can she be retaining? can we be retaining? can you be retaining? can they be retaining?
Perfect	V-ing perfect
can I have retained? can you have retained? can she have retained? can we have retained? can you have retained? can they have retained?	can I have been retaining? can you have been retaining? can she have been retaining? can we have been retaining? can you have been retaining? can they have been retaining?

Interro-negative form

Simple form	V-ing form
can I not retain? can you not retain? can she not retain? can we not retain? can you not retain? can they not retain?	can I not be retaining? can you not be retaining? can she not be retaining? can we not be retaining? can you not be retaining? can they not be retaining?
Perfect	V-ing perfect
can I not have retained? can you not have retained? can she not have retained? can we not have retained? can you not have retained? can they not have retained?	can I not have been retaining? can you not have been retaining? can she not have been retaining? can we not have been retaining? can you not have been retaining? can they not have been retaining?