could grubstake
Regular verb: grubstake - grubstaked- grubstaked

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could grubstake
you could grubstake
she could grubstake
we could grubstake
you could grubstake
they could grubstake 	I could be grubstaking
you could be grubstaking
she could be grubstaking
we could be grubstaking
you could be grubstaking
they could be grubstaking	I could have grubstaked
you could have grubstaked
she could have grubstaked
we could have grubstaked
you could have grubstaked
they could have grubstaked	I could have been grubstaking
you could have been grubstaking
she could have been grubstaking
we could have been grubstaking
you could have been grubstaking
they could have been grubstaking	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not grubstake
you could not grubstake
she could not grubstake
we could not grubstake
you could not grubstake
they could not grubstake 	I could not be grubstaking
you could not be grubstaking
she could not be grubstaking
we could not be grubstaking
you could not be grubstaking
they could not be grubstaking	I could not have grubstaked
you could not have grubstaked
she could not have grubstaked
we could not have grubstaked
you could not have grubstaked
they could not have grubstaked	I could not have been grubstaking
you could not have been grubstaking
she could not have been grubstaking
we could not have been grubstaking
you could not have been grubstaking
they could not have been grubstaking	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I grubstake?
could you grubstake?
could she grubstake?
could we grubstake?
could you grubstake?
could they grubstake? 	could I be grubstaking?
could you be grubstaking?
could she be grubstaking?
could we be grubstaking?
could you be grubstaking?
could they be grubstaking? 	could I have grubstaked?
could you have grubstaked?
could she have grubstaked?
could we have grubstaked?
could you have grubstaked?
could they have grubstaked? 	could I have been grubstaking?
could you have been grubstaking?
could she have been grubstaking?
could we have been grubstaking?
could you have been grubstaking?
could they have been grubstaking? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not grubstake?
could you not grubstake?
could she not grubstake?
could we not grubstake?
could you not grubstake?
could they not grubstake? 	could I not be grubstaking?
could you not be grubstaking?
could she not be grubstaking?
could we not be grubstaking?
could you not be grubstaking?
could they not be grubstaking? 	could I not have grubstaked?
could you not have grubstaked?
could she not have grubstaked?
could we not have grubstaked?
could you not have grubstaked?
could they not have grubstaked? 	could I not have been grubstaking?
could you not have been grubstaking?
could she not have been grubstaking?
could we not have been grubstaking?
could you not have been grubstaking?
could they not have been grubstaking?