I can design you can design he can design we can design you can design they can design
V-ing form
I can be designing you can be designing he can be designing we can be designing you can be designing they can be designing
Perfect
I can have designed you can have designed he can have designed we can have designed you can have designed they can have designed
V-ing perfect
I can have been designing you can have been designing he can have been designing we can have been designing you can have been designing they can have been designing
Negation
Simple form
I can't design you can't design he can't design we can't design you can't design they can't design
V-ing form
I can't be designing you can't be designing he can't be designing we can't be designing you can't be designing they can't be designing
Perfect
I can't have designed you can't have designed he can't have designed we can't have designed you can't have designed they can't have designed
V-ing perfect
I can't have been designing you can't have been designing he can't have been designing we can't have been designing you can't have been designing they can't have been designing
Interrogative form
Simple form
can I design? can you design? can he design? can we design? can you design? can they design?
V-ing form
can I be designing? can you be designing? can he be designing? can we be designing? can you be designing? can they be designing?
Perfect
can I have designed? can you have designed? can he have designed? can we have designed? can you have designed? can they have designed?
V-ing perfect
can I have been designing? can you have been designing? can he have been designing? can we have been designing? can you have been designing? can they have been designing?
Interro-negative form
Simple form
can't I design? can't you design? can't he design? can't we design? can't you design? can't they design?
V-ing form
can't I be designing? can't you be designing? can't he be designing? can't we be designing? can't you be designing? can't they be designing?
Perfect
can't I have designed? can't you have designed? can't he have designed? can't we have designed? can't you have designed? can't they have designed?
V-ing perfect
can't I have been designing? can't you have been designing? can't he have been designing? can't we have been designing? can't you have been designing? can't they have been designing?