I could justify you could justify he could justify we could justify you could justify they could justify
V-ing form
I could be justifying you could be justifying he could be justifying we could be justifying you could be justifying they could be justifying
Perfect
I could have justified you could have justified he could have justified we could have justified you could have justified they could have justified
V-ing perfect
I could have been justifying you could have been justifying he could have been justifying we could have been justifying you could have been justifying they could have been justifying
Negation
Simple form
I couldn't justify you couldn't justify he couldn't justify we couldn't justify you couldn't justify they couldn't justify
V-ing form
I couldn't be justifying you couldn't be justifying he couldn't be justifying we couldn't be justifying you couldn't be justifying they couldn't be justifying
Perfect
I couldn't have justified you couldn't have justified he couldn't have justified we couldn't have justified you couldn't have justified they couldn't have justified
V-ing perfect
I couldn't have been justifying you couldn't have been justifying he couldn't have been justifying we couldn't have been justifying you couldn't have been justifying they couldn't have been justifying
Interrogative form
Simple form
could I justify? could you justify? could he justify? could we justify? could you justify? could they justify?
V-ing form
could I be justifying? could you be justifying? could he be justifying? could we be justifying? could you be justifying? could they be justifying?
Perfect
could I have justified? could you have justified? could he have justified? could we have justified? could you have justified? could they have justified?
V-ing perfect
could I have been justifying? could you have been justifying? could he have been justifying? could we have been justifying? could you have been justifying? could they have been justifying?
Interro-negative form
Simple form
couldn't I justify? couldn't you justify? couldn't he justify? couldn't we justify? couldn't you justify? couldn't they justify?
V-ing form
couldn't I be justifying? couldn't you be justifying? couldn't he be justifying? couldn't we be justifying? couldn't you be justifying? couldn't they be justifying?
Perfect
couldn't I have justified? couldn't you have justified? couldn't he have justified? couldn't we have justified? couldn't you have justified? couldn't they have justified?
V-ing perfect
couldn't I have been justifying? couldn't you have been justifying? couldn't he have been justifying? couldn't we have been justifying? couldn't you have been justifying? couldn't they have been justifying?