English verb conjugation
CAN RETRIEVE

Regular verb: retrieve - retrieved - retrieved

Affirmation

Simple form	V-ing form
I can retrieve you can retrieve he can retrieve we can retrieve you can retrieve they can retrieve	I can be retrieving you can be retrieving he can be retrieving we can be retrieving you can be retrieving they can be retrieving
Perfect	V-ing perfect
I can have retrieved you can have retrieved he can have retrieved we can have retrieved you can have retrieved they can have retrieved	I can have been retrieving you can have been retrieving he can have been retrieving we can have been retrieving you can have been retrieving they can have been retrieving

Negation

Simple form	V-ing form
I cannot retrieve you cannot retrieve he cannot retrieve we cannot retrieve you cannot retrieve they cannot retrieve	I cannot be retrieving you cannot be retrieving he cannot be retrieving we cannot be retrieving you cannot be retrieving they cannot be retrieving
Perfect	V-ing perfect
I cannot have retrieved you cannot have retrieved he cannot have retrieved we cannot have retrieved you cannot have retrieved they cannot have retrieved	I cannot have been retrieving you cannot have been retrieving he cannot have been retrieving we cannot have been retrieving you cannot have been retrieving they cannot have been retrieving

Interrogative form

Simple form	V-ing form
can I retrieve? can you retrieve? can he retrieve? can we retrieve? can you retrieve? can they retrieve?	can I be retrieving? can you be retrieving? can he be retrieving? can we be retrieving? can you be retrieving? can they be retrieving?
Perfect	V-ing perfect
can I have retrieved? can you have retrieved? can he have retrieved? can we have retrieved? can you have retrieved? can they have retrieved?	can I have been retrieving? can you have been retrieving? can he have been retrieving? can we have been retrieving? can you have been retrieving? can they have been retrieving?

Interro-negative form

Simple form	V-ing form
can I not retrieve? can you not retrieve? can he not retrieve? can we not retrieve? can you not retrieve? can they not retrieve?	can I not be retrieving? can you not be retrieving? can he not be retrieving? can we not be retrieving? can you not be retrieving? can they not be retrieving?
Perfect	V-ing perfect
can I not have retrieved? can you not have retrieved? can he not have retrieved? can we not have retrieved? can you not have retrieved? can they not have retrieved?	can I not have been retrieving? can you not have been retrieving? can he not have been retrieving? can we not have been retrieving? can you not have been retrieving? can they not have been retrieving?