could petrify
Regular verb: petrify - petrified- petrified

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could petrify
you could petrify
he could petrify
we could petrify
you could petrify
they could petrify 	I could be petrifying
you could be petrifying
he could be petrifying
we could be petrifying
you could be petrifying
they could be petrifying	I could have petrified
you could have petrified
he could have petrified
we could have petrified
you could have petrified
they could have petrified	I could have been petrifying
you could have been petrifying
he could have been petrifying
we could have been petrifying
you could have been petrifying
they could have been petrifying	

Negation 	
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I couldn't petrify
you couldn't petrify
he couldn't petrify
we couldn't petrify
you couldn't petrify
they couldn't petrify 	I couldn't be petrifying
you couldn't be petrifying
he couldn't be petrifying
we couldn't be petrifying
you couldn't be petrifying
they couldn't be petrifying	I couldn't have petrified
you couldn't have petrified
he couldn't have petrified
we couldn't have petrified
you couldn't have petrified
they couldn't have petrified	I couldn't have been petrifying
you couldn't have been petrifying
he couldn't have been petrifying
we couldn't have been petrifying
you couldn't have been petrifying
they couldn't have been petrifying	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I petrify?
could you petrify?
could he petrify?
could we petrify?
could you petrify?
could they petrify? 	could I be petrifying?
could you be petrifying?
could he be petrifying?
could we be petrifying?
could you be petrifying?
could they be petrifying? 	could I have petrified?
could you have petrified?
could he have petrified?
could we have petrified?
could you have petrified?
could they have petrified? 	could I have been petrifying?
could you have been petrifying?
could he have been petrifying?
could we have been petrifying?
could you have been petrifying?
could they have been petrifying? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I petrify?
couldn't you petrify?
couldn't he petrify?
couldn't we petrify?
couldn't you petrify?
couldn't they petrify? 	couldn't I be petrifying?
couldn't you be petrifying?
couldn't he be petrifying?
couldn't we be petrifying?
couldn't you be petrifying?
couldn't they be petrifying? 	couldn't I have petrified?
couldn't you have petrified?
couldn't he have petrified?
couldn't we have petrified?
couldn't you have petrified?
couldn't they have petrified? 	couldn't I have been petrifying?
couldn't you have been petrifying?
couldn't he have been petrifying?
couldn't we have been petrifying?
couldn't you have been petrifying?
couldn't they have been petrifying?