I should retard you should retard he should retard we should retard you should retard they should retard
V-ing form
I should be retarding you should be retarding he should be retarding we should be retarding you should be retarding they should be retarding
Perfect
I should have retarded you should have retarded he should have retarded we should have retarded you should have retarded they should have retarded
V-ing perfect
I should have been retarding you should have been retarding he should have been retarding we should have been retarding you should have been retarding they should have been retarding
Negation
Simple form
I should not retard you should not retard he should not retard we should not retard you should not retard they should not retard
V-ing form
I should not be retarding you should not be retarding he should not be retarding we should not be retarding you should not be retarding they should not be retarding
Perfect
I should not have retarded you should not have retarded he should not have retarded we should not have retarded you should not have retarded they should not have retarded
V-ing perfect
I should not have been retarding you should not have been retarding he should not have been retarding we should not have been retarding you should not have been retarding they should not have been retarding
Interrogative form
Simple form
should I retard? should you retard? should he retard? should we retard? should you retard? should they retard?
V-ing form
should I be retarding? should you be retarding? should he be retarding? should we be retarding? should you be retarding? should they be retarding?
Perfect
should I have retarded? should you have retarded? should he have retarded? should we have retarded? should you have retarded? should they have retarded?
V-ing perfect
should I have been retarding? should you have been retarding? should he have been retarding? should we have been retarding? should you have been retarding? should they have been retarding?
Interro-negative form
Simple form
should I not retard? should you not retard? should he not retard? should we not retard? should you not retard? should they not retard?
V-ing form
should I not be retarding? should you not be retarding? should he not be retarding? should we not be retarding? should you not be retarding? should they not be retarding?
Perfect
should I not have retarded? should you not have retarded? should he not have retarded? should we not have retarded? should you not have retarded? should they not have retarded?
V-ing perfect
should I not have been retarding? should you not have been retarding? should he not have been retarding? should we not have been retarding? should you not have been retarding? should they not have been retarding?