can inquire
Regular verb: inquire - inquired- inquired

Affirmation 	
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I can inquire
you can inquire
he can inquire
we can inquire
you can inquire
they can inquire 	I can be inquiring
you can be inquiring
he can be inquiring
we can be inquiring
you can be inquiring
they can be inquiring	I can have inquired
you can have inquired
he can have inquired
we can have inquired
you can have inquired
they can have inquired	I can have been inquiring
you can have been inquiring
he can have been inquiring
we can have been inquiring
you can have been inquiring
they can have been inquiring	

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

Interrogative form 	
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can I inquire?
can you inquire?
can he inquire?
can we inquire?
can you inquire?
can they inquire? 	can I be inquiring?
can you be inquiring?
can he be inquiring?
can we be inquiring?
can you be inquiring?
can they be inquiring? 	can I have inquired?
can you have inquired?
can he have inquired?
can we have inquired?
can you have inquired?
can they have inquired? 	can I have been inquiring?
can you have been inquiring?
can he have been inquiring?
can we have been inquiring?
can you have been inquiring?
can they have been inquiring? 	

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