could fortify
Regular verb: fortify - fortified- fortified

Affirmation 	
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I could fortify
you could fortify
he could fortify
we could fortify
you could fortify
they could fortify 	I could be fortifying
you could be fortifying
he could be fortifying
we could be fortifying
you could be fortifying
they could be fortifying	I could have fortified
you could have fortified
he could have fortified
we could have fortified
you could have fortified
they could have fortified	I could have been fortifying
you could have been fortifying
he could have been fortifying
we could have been fortifying
you could have been fortifying
they could have been fortifying	

Negation 	
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I couldn't fortify
you couldn't fortify
he couldn't fortify
we couldn't fortify
you couldn't fortify
they couldn't fortify 	I couldn't be fortifying
you couldn't be fortifying
he couldn't be fortifying
we couldn't be fortifying
you couldn't be fortifying
they couldn't be fortifying	I couldn't have fortified
you couldn't have fortified
he couldn't have fortified
we couldn't have fortified
you couldn't have fortified
they couldn't have fortified	I couldn't have been fortifying
you couldn't have been fortifying
he couldn't have been fortifying
we couldn't have been fortifying
you couldn't have been fortifying
they couldn't have been fortifying	

Interrogative form 	
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could I fortify?
could you fortify?
could he fortify?
could we fortify?
could you fortify?
could they fortify? 	could I be fortifying?
could you be fortifying?
could he be fortifying?
could we be fortifying?
could you be fortifying?
could they be fortifying? 	could I have fortified?
could you have fortified?
could he have fortified?
could we have fortified?
could you have fortified?
could they have fortified? 	could I have been fortifying?
could you have been fortifying?
could he have been fortifying?
could we have been fortifying?
could you have been fortifying?
could they have been fortifying? 	

Interro-negative form 	
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couldn't I fortify?
couldn't you fortify?
couldn't he fortify?
couldn't we fortify?
couldn't you fortify?
couldn't they fortify? 	couldn't I be fortifying?
couldn't you be fortifying?
couldn't he be fortifying?
couldn't we be fortifying?
couldn't you be fortifying?
couldn't they be fortifying? 	couldn't I have fortified?
couldn't you have fortified?
couldn't he have fortified?
couldn't we have fortified?
couldn't you have fortified?
couldn't they have fortified? 	couldn't I have been fortifying?
couldn't you have been fortifying?
couldn't he have been fortifying?
couldn't we have been fortifying?
couldn't you have been fortifying?
couldn't they have been fortifying?