could testify
Regular verb: testify - testified- testified

Affirmation 	
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I could testify
you could testify
she could testify
we could testify
you could testify
they could testify 	I could be testifying
you could be testifying
she could be testifying
we could be testifying
you could be testifying
they could be testifying	I could have testified
you could have testified
she could have testified
we could have testified
you could have testified
they could have testified	I could have been testifying
you could have been testifying
she could have been testifying
we could have been testifying
you could have been testifying
they could have been testifying	

Negation 	
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I could not testify
you could not testify
she could not testify
we could not testify
you could not testify
they could not testify 	I could not be testifying
you could not be testifying
she could not be testifying
we could not be testifying
you could not be testifying
they could not be testifying	I could not have testified
you could not have testified
she could not have testified
we could not have testified
you could not have testified
they could not have testified	I could not have been testifying
you could not have been testifying
she could not have been testifying
we could not have been testifying
you could not have been testifying
they could not have been testifying	

Interrogative form 	
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could I testify?
could you testify?
could she testify?
could we testify?
could you testify?
could they testify? 	could I be testifying?
could you be testifying?
could she be testifying?
could we be testifying?
could you be testifying?
could they be testifying? 	could I have testified?
could you have testified?
could she have testified?
could we have testified?
could you have testified?
could they have testified? 	could I have been testifying?
could you have been testifying?
could she have been testifying?
could we have been testifying?
could you have been testifying?
could they have been testifying? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not testify?
could you not testify?
could she not testify?
could we not testify?
could you not testify?
could they not testify? 	could I not be testifying?
could you not be testifying?
could she not be testifying?
could we not be testifying?
could you not be testifying?
could they not be testifying? 	could I not have testified?
could you not have testified?
could she not have testified?
could we not have testified?
could you not have testified?
could they not have testified? 	could I not have been testifying?
could you not have been testifying?
could she not have been testifying?
could we not have been testifying?
could you not have been testifying?
could they not have been testifying?