could inquire
Regular verb: inquire - inquired- inquired

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could inquire
you could inquire
he could inquire
we could inquire
you could inquire
they could inquire 	I could be inquiring
you could be inquiring
he could be inquiring
we could be inquiring
you could be inquiring
they could be inquiring	I could have inquired
you could have inquired
he could have inquired
we could have inquired
you could have inquired
they could have inquired	I could have been inquiring
you could have been inquiring
he could have been inquiring
we could have been inquiring
you could have been inquiring
they could have been inquiring	

Negation 	
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I couldn't inquire
you couldn't inquire
he couldn't inquire
we couldn't inquire
you couldn't inquire
they couldn't inquire 	I couldn't be inquiring
you couldn't be inquiring
he couldn't be inquiring
we couldn't be inquiring
you couldn't be inquiring
they couldn't be inquiring	I couldn't have inquired
you couldn't have inquired
he couldn't have inquired
we couldn't have inquired
you couldn't have inquired
they couldn't have inquired	I couldn't have been inquiring
you couldn't have been inquiring
he couldn't have been inquiring
we couldn't have been inquiring
you couldn't have been inquiring
they couldn't have been inquiring	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I inquire?
could you inquire?
could he inquire?
could we inquire?
could you inquire?
could they inquire? 	could I be inquiring?
could you be inquiring?
could he be inquiring?
could we be inquiring?
could you be inquiring?
could they be inquiring? 	could I have inquired?
could you have inquired?
could he have inquired?
could we have inquired?
could you have inquired?
could they have inquired? 	could I have been inquiring?
could you have been inquiring?
could he have been inquiring?
could we have been inquiring?
could you have been inquiring?
could they have been inquiring? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I inquire?
couldn't you inquire?
couldn't he inquire?
couldn't we inquire?
couldn't you inquire?
couldn't they inquire? 	couldn't I be inquiring?
couldn't you be inquiring?
couldn't he be inquiring?
couldn't we be inquiring?
couldn't you be inquiring?
couldn't they be inquiring? 	couldn't I have inquired?
couldn't you have inquired?
couldn't he have inquired?
couldn't we have inquired?
couldn't you have inquired?
couldn't they have inquired? 	couldn't I have been inquiring?
couldn't you have been inquiring?
couldn't he have been inquiring?
couldn't we have been inquiring?
couldn't you have been inquiring?
couldn't they have been inquiring?