I should base you should base she should base we should base you should base they should base
V-ing form
I should be basing you should be basing she should be basing we should be basing you should be basing they should be basing
Perfect
I should have based you should have based she should have based we should have based you should have based they should have based
V-ing perfect
I should have been basing you should have been basing she should have been basing we should have been basing you should have been basing they should have been basing
Negation
Simple form
I should not base you should not base she should not base we should not base you should not base they should not base
V-ing form
I should not be basing you should not be basing she should not be basing we should not be basing you should not be basing they should not be basing
Perfect
I should not have based you should not have based she should not have based we should not have based you should not have based they should not have based
V-ing perfect
I should not have been basing you should not have been basing she should not have been basing we should not have been basing you should not have been basing they should not have been basing
Interrogative form
Simple form
should I base? should you base? should she base? should we base? should you base? should they base?
V-ing form
should I be basing? should you be basing? should she be basing? should we be basing? should you be basing? should they be basing?
Perfect
should I have based? should you have based? should she have based? should we have based? should you have based? should they have based?
V-ing perfect
should I have been basing? should you have been basing? should she have been basing? should we have been basing? should you have been basing? should they have been basing?
Interro-negative form
Simple form
should I not base? should you not base? should she not base? should we not base? should you not base? should they not base?
V-ing form
should I not be basing? should you not be basing? should she not be basing? should we not be basing? should you not be basing? should they not be basing?
Perfect
should I not have based? should you not have based? should she not have based? should we not have based? should you not have based? should they not have based?
V-ing perfect
should I not have been basing? should you not have been basing? should she not have been basing? should we not have been basing? should you not have been basing? should they not have been basing?