could detect
Regular verb: detect - detected- detected

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could detect
you could detect
he could detect
we could detect
you could detect
they could detect 	I could be detecting
you could be detecting
he could be detecting
we could be detecting
you could be detecting
they could be detecting	I could have detected
you could have detected
he could have detected
we could have detected
you could have detected
they could have detected	I could have been detecting
you could have been detecting
he could have been detecting
we could have been detecting
you could have been detecting
they could have been detecting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not detect
you could not detect
he could not detect
we could not detect
you could not detect
they could not detect 	I could not be detecting
you could not be detecting
he could not be detecting
we could not be detecting
you could not be detecting
they could not be detecting	I could not have detected
you could not have detected
he could not have detected
we could not have detected
you could not have detected
they could not have detected	I could not have been detecting
you could not have been detecting
he could not have been detecting
we could not have been detecting
you could not have been detecting
they could not have been detecting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I detect?
could you detect?
could he detect?
could we detect?
could you detect?
could they detect? 	could I be detecting?
could you be detecting?
could he be detecting?
could we be detecting?
could you be detecting?
could they be detecting? 	could I have detected?
could you have detected?
could he have detected?
could we have detected?
could you have detected?
could they have detected? 	could I have been detecting?
could you have been detecting?
could he have been detecting?
could we have been detecting?
could you have been detecting?
could they have been detecting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not detect?
could you not detect?
could he not detect?
could we not detect?
could you not detect?
could they not detect? 	could I not be detecting?
could you not be detecting?
could he not be detecting?
could we not be detecting?
could you not be detecting?
could they not be detecting? 	could I not have detected?
could you not have detected?
could he not have detected?
could we not have detected?
could you not have detected?
could they not have detected? 	could I not have been detecting?
could you not have been detecting?
could he not have been detecting?
could we not have been detecting?
could you not have been detecting?
could they not have been detecting?