could ossify
Regular verb: ossify - ossified- ossified

Affirmation 	
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I could ossify
you could ossify
he could ossify
we could ossify
you could ossify
they could ossify 	I could be ossifying
you could be ossifying
he could be ossifying
we could be ossifying
you could be ossifying
they could be ossifying	I could have ossified
you could have ossified
he could have ossified
we could have ossified
you could have ossified
they could have ossified	I could have been ossifying
you could have been ossifying
he could have been ossifying
we could have been ossifying
you could have been ossifying
they could have been ossifying	

Negation 	
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I couldn't ossify
you couldn't ossify
he couldn't ossify
we couldn't ossify
you couldn't ossify
they couldn't ossify 	I couldn't be ossifying
you couldn't be ossifying
he couldn't be ossifying
we couldn't be ossifying
you couldn't be ossifying
they couldn't be ossifying	I couldn't have ossified
you couldn't have ossified
he couldn't have ossified
we couldn't have ossified
you couldn't have ossified
they couldn't have ossified	I couldn't have been ossifying
you couldn't have been ossifying
he couldn't have been ossifying
we couldn't have been ossifying
you couldn't have been ossifying
they couldn't have been ossifying	

Interrogative form 	
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could I ossify?
could you ossify?
could he ossify?
could we ossify?
could you ossify?
could they ossify? 	could I be ossifying?
could you be ossifying?
could he be ossifying?
could we be ossifying?
could you be ossifying?
could they be ossifying? 	could I have ossified?
could you have ossified?
could he have ossified?
could we have ossified?
could you have ossified?
could they have ossified? 	could I have been ossifying?
could you have been ossifying?
could he have been ossifying?
could we have been ossifying?
could you have been ossifying?
could they have been ossifying? 	

Interro-negative form 	
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couldn't I ossify?
couldn't you ossify?
couldn't he ossify?
couldn't we ossify?
couldn't you ossify?
couldn't they ossify? 	couldn't I be ossifying?
couldn't you be ossifying?
couldn't he be ossifying?
couldn't we be ossifying?
couldn't you be ossifying?
couldn't they be ossifying? 	couldn't I have ossified?
couldn't you have ossified?
couldn't he have ossified?
couldn't we have ossified?
couldn't you have ossified?
couldn't they have ossified? 	couldn't I have been ossifying?
couldn't you have been ossifying?
couldn't he have been ossifying?
couldn't we have been ossifying?
couldn't you have been ossifying?
couldn't they have been ossifying?