I can grasp you can grasp he can grasp we can grasp you can grasp they can grasp
V-ing form
I can be grasping you can be grasping he can be grasping we can be grasping you can be grasping they can be grasping
Perfect
I can have grasped you can have grasped he can have grasped we can have grasped you can have grasped they can have grasped
V-ing perfect
I can have been grasping you can have been grasping he can have been grasping we can have been grasping you can have been grasping they can have been grasping
Negation
Simple form
I can't grasp you can't grasp he can't grasp we can't grasp you can't grasp they can't grasp
V-ing form
I can't be grasping you can't be grasping he can't be grasping we can't be grasping you can't be grasping they can't be grasping
Perfect
I can't have grasped you can't have grasped he can't have grasped we can't have grasped you can't have grasped they can't have grasped
V-ing perfect
I can't have been grasping you can't have been grasping he can't have been grasping we can't have been grasping you can't have been grasping they can't have been grasping
Interrogative form
Simple form
can I grasp? can you grasp? can he grasp? can we grasp? can you grasp? can they grasp?
V-ing form
can I be grasping? can you be grasping? can he be grasping? can we be grasping? can you be grasping? can they be grasping?
Perfect
can I have grasped? can you have grasped? can he have grasped? can we have grasped? can you have grasped? can they have grasped?
V-ing perfect
can I have been grasping? can you have been grasping? can he have been grasping? can we have been grasping? can you have been grasping? can they have been grasping?
Interro-negative form
Simple form
can't I grasp? can't you grasp? can't he grasp? can't we grasp? can't you grasp? can't they grasp?
V-ing form
can't I be grasping? can't you be grasping? can't he be grasping? can't we be grasping? can't you be grasping? can't they be grasping?
Perfect
can't I have grasped? can't you have grasped? can't he have grasped? can't we have grasped? can't you have grasped? can't they have grasped?
V-ing perfect
can't I have been grasping? can't you have been grasping? can't he have been grasping? can't we have been grasping? can't you have been grasping? can't they have been grasping?