I can bump you can bump he can bump we can bump you can bump they can bump
V-ing form
I can be bumping you can be bumping he can be bumping we can be bumping you can be bumping they can be bumping
Perfect
I can have bumped you can have bumped he can have bumped we can have bumped you can have bumped they can have bumped
V-ing perfect
I can have been bumping you can have been bumping he can have been bumping we can have been bumping you can have been bumping they can have been bumping
Negation
Simple form
I can't bump you can't bump he can't bump we can't bump you can't bump they can't bump
V-ing form
I can't be bumping you can't be bumping he can't be bumping we can't be bumping you can't be bumping they can't be bumping
Perfect
I can't have bumped you can't have bumped he can't have bumped we can't have bumped you can't have bumped they can't have bumped
V-ing perfect
I can't have been bumping you can't have been bumping he can't have been bumping we can't have been bumping you can't have been bumping they can't have been bumping
Interrogative form
Simple form
can I bump? can you bump? can he bump? can we bump? can you bump? can they bump?
V-ing form
can I be bumping? can you be bumping? can he be bumping? can we be bumping? can you be bumping? can they be bumping?
Perfect
can I have bumped? can you have bumped? can he have bumped? can we have bumped? can you have bumped? can they have bumped?
V-ing perfect
can I have been bumping? can you have been bumping? can he have been bumping? can we have been bumping? can you have been bumping? can they have been bumping?
Interro-negative form
Simple form
can't I bump? can't you bump? can't he bump? can't we bump? can't you bump? can't they bump?
V-ing form
can't I be bumping? can't you be bumping? can't he be bumping? can't we be bumping? can't you be bumping? can't they be bumping?
Perfect
can't I have bumped? can't you have bumped? can't he have bumped? can't we have bumped? can't you have bumped? can't they have bumped?
V-ing perfect
can't I have been bumping? can't you have been bumping? can't he have been bumping? can't we have been bumping? can't you have been bumping? can't they have been bumping?