could petition
Regular verb: petition - petitioned- petitioned

Affirmation 	
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I could petition
you could petition
she could petition
we could petition
you could petition
they could petition 	I could be petitioning
you could be petitioning
she could be petitioning
we could be petitioning
you could be petitioning
they could be petitioning	I could have petitioned
you could have petitioned
she could have petitioned
we could have petitioned
you could have petitioned
they could have petitioned	I could have been petitioning
you could have been petitioning
she could have been petitioning
we could have been petitioning
you could have been petitioning
they could have been petitioning	

Negation 	
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I couldn't petition
you couldn't petition
she couldn't petition
we couldn't petition
you couldn't petition
they couldn't petition 	I couldn't be petitioning
you couldn't be petitioning
she couldn't be petitioning
we couldn't be petitioning
you couldn't be petitioning
they couldn't be petitioning	I couldn't have petitioned
you couldn't have petitioned
she couldn't have petitioned
we couldn't have petitioned
you couldn't have petitioned
they couldn't have petitioned	I couldn't have been petitioning
you couldn't have been petitioning
she couldn't have been petitioning
we couldn't have been petitioning
you couldn't have been petitioning
they couldn't have been petitioning	

Interrogative form 	
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could I petition?
could you petition?
could she petition?
could we petition?
could you petition?
could they petition? 	could I be petitioning?
could you be petitioning?
could she be petitioning?
could we be petitioning?
could you be petitioning?
could they be petitioning? 	could I have petitioned?
could you have petitioned?
could she have petitioned?
could we have petitioned?
could you have petitioned?
could they have petitioned? 	could I have been petitioning?
could you have been petitioning?
could she have been petitioning?
could we have been petitioning?
could you have been petitioning?
could they have been petitioning? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I petition?
couldn't you petition?
couldn't she petition?
couldn't we petition?
couldn't you petition?
couldn't they petition? 	couldn't I be petitioning?
couldn't you be petitioning?
couldn't she be petitioning?
couldn't we be petitioning?
couldn't you be petitioning?
couldn't they be petitioning? 	couldn't I have petitioned?
couldn't you have petitioned?
couldn't she have petitioned?
couldn't we have petitioned?
couldn't you have petitioned?
couldn't they have petitioned? 	couldn't I have been petitioning?
couldn't you have been petitioning?
couldn't she have been petitioning?
couldn't we have been petitioning?
couldn't you have been petitioning?
couldn't they have been petitioning?