can grump
Regular verb: grump - grumped- grumped

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can grump
you can grump
he can grump
we can grump
you can grump
they can grump 	I can be grumping
you can be grumping
he can be grumping
we can be grumping
you can be grumping
they can be grumping	I can have grumped
you can have grumped
he can have grumped
we can have grumped
you can have grumped
they can have grumped	I can have been grumping
you can have been grumping
he can have been grumping
we can have been grumping
you can have been grumping
they can have been grumping	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I cannot grump
you cannot grump
he cannot grump
we cannot grump
you cannot grump
they cannot grump 	I cannot be grumping
you cannot be grumping
he cannot be grumping
we cannot be grumping
you cannot be grumping
they cannot be grumping	I cannot have grumped
you cannot have grumped
he cannot have grumped
we cannot have grumped
you cannot have grumped
they cannot have grumped	I cannot have been grumping
you cannot have been grumping
he cannot have been grumping
we cannot have been grumping
you cannot have been grumping
they cannot have been grumping	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I grump?
can you grump?
can he grump?
can we grump?
can you grump?
can they grump? 	can I be grumping?
can you be grumping?
can he be grumping?
can we be grumping?
can you be grumping?
can they be grumping? 	can I have grumped?
can you have grumped?
can he have grumped?
can we have grumped?
can you have grumped?
can they have grumped? 	can I have been grumping?
can you have been grumping?
can he have been grumping?
can we have been grumping?
can you have been grumping?
can they have been grumping? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I not grump?
can you not grump?
can he not grump?
can we not grump?
can you not grump?
can they not grump? 	can I not be grumping?
can you not be grumping?
can he not be grumping?
can we not be grumping?
can you not be grumping?
can they not be grumping? 	can I not have grumped?
can you not have grumped?
can he not have grumped?
can we not have grumped?
can you not have grumped?
can they not have grumped? 	can I not have been grumping?
can you not have been grumping?
can he not have been grumping?
can we not have been grumping?
can you not have been grumping?
can they not have been grumping?