could preinvestigate preinvestigate
Regular verb: preinvestigate preinvestigate - preinvestigate preinvestigated- preinvestigate preinvestigated

, this verb may not exist. Conjugation is given as example.

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could preinvestigate preinvestigate
you could preinvestigate preinvestigate
she could preinvestigate preinvestigate
we could preinvestigate preinvestigate
you could preinvestigate preinvestigate
they could preinvestigate preinvestigate 	I could be preinvestigate preinvestigating
you could be preinvestigate preinvestigating
she could be preinvestigate preinvestigating
we could be preinvestigate preinvestigating
you could be preinvestigate preinvestigating
they could be preinvestigate preinvestigating	I could have preinvestigate preinvestigated
you could have preinvestigate preinvestigated
she could have preinvestigate preinvestigated
we could have preinvestigate preinvestigated
you could have preinvestigate preinvestigated
they could have preinvestigate preinvestigated	I could have been preinvestigate preinvestigating
you could have been preinvestigate preinvestigating
she could have been preinvestigate preinvestigating
we could have been preinvestigate preinvestigating
you could have been preinvestigate preinvestigating
they could have been preinvestigate preinvestigating	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't preinvestigate preinvestigate
you couldn't preinvestigate preinvestigate
she couldn't preinvestigate preinvestigate
we couldn't preinvestigate preinvestigate
you couldn't preinvestigate preinvestigate
they couldn't preinvestigate preinvestigate 	I couldn't be preinvestigate preinvestigating
you couldn't be preinvestigate preinvestigating
she couldn't be preinvestigate preinvestigating
we couldn't be preinvestigate preinvestigating
you couldn't be preinvestigate preinvestigating
they couldn't be preinvestigate preinvestigating	I couldn't have preinvestigate preinvestigated
you couldn't have preinvestigate preinvestigated
she couldn't have preinvestigate preinvestigated
we couldn't have preinvestigate preinvestigated
you couldn't have preinvestigate preinvestigated
they couldn't have preinvestigate preinvestigated	I couldn't have been preinvestigate preinvestigating
you couldn't have been preinvestigate preinvestigating
she couldn't have been preinvestigate preinvestigating
we couldn't have been preinvestigate preinvestigating
you couldn't have been preinvestigate preinvestigating
they couldn't have been preinvestigate preinvestigating	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I preinvestigate preinvestigate?
could you preinvestigate preinvestigate?
could she preinvestigate preinvestigate?
could we preinvestigate preinvestigate?
could you preinvestigate preinvestigate?
could they preinvestigate preinvestigate? 	could I be preinvestigate preinvestigating?
could you be preinvestigate preinvestigating?
could she be preinvestigate preinvestigating?
could we be preinvestigate preinvestigating?
could you be preinvestigate preinvestigating?
could they be preinvestigate preinvestigating? 	could I have preinvestigate preinvestigated?
could you have preinvestigate preinvestigated?
could she have preinvestigate preinvestigated?
could we have preinvestigate preinvestigated?
could you have preinvestigate preinvestigated?
could they have preinvestigate preinvestigated? 	could I have been preinvestigate preinvestigating?
could you have been preinvestigate preinvestigating?
could she have been preinvestigate preinvestigating?
could we have been preinvestigate preinvestigating?
could you have been preinvestigate preinvestigating?
could they have been preinvestigate preinvestigating? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I preinvestigate preinvestigate?
couldn't you preinvestigate preinvestigate?
couldn't she preinvestigate preinvestigate?
couldn't we preinvestigate preinvestigate?
couldn't you preinvestigate preinvestigate?
couldn't they preinvestigate preinvestigate? 	couldn't I be preinvestigate preinvestigating?
couldn't you be preinvestigate preinvestigating?
couldn't she be preinvestigate preinvestigating?
couldn't we be preinvestigate preinvestigating?
couldn't you be preinvestigate preinvestigating?
couldn't they be preinvestigate preinvestigating? 	couldn't I have preinvestigate preinvestigated?
couldn't you have preinvestigate preinvestigated?
couldn't she have preinvestigate preinvestigated?
couldn't we have preinvestigate preinvestigated?
couldn't you have preinvestigate preinvestigated?
couldn't they have preinvestigate preinvestigated? 	couldn't I have been preinvestigate preinvestigating?
couldn't you have been preinvestigate preinvestigating?
couldn't she have been preinvestigate preinvestigating?
couldn't we have been preinvestigate preinvestigating?
couldn't you have been preinvestigate preinvestigating?
couldn't they have been preinvestigate preinvestigating?