could execute
Regular verb: execute - executed- executed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could execute
you could execute
she could execute
we could execute
you could execute
they could execute 	I could be executing
you could be executing
she could be executing
we could be executing
you could be executing
they could be executing	I could have executed
you could have executed
she could have executed
we could have executed
you could have executed
they could have executed	I could have been executing
you could have been executing
she could have been executing
we could have been executing
you could have been executing
they could have been executing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not execute
you could not execute
she could not execute
we could not execute
you could not execute
they could not execute 	I could not be executing
you could not be executing
she could not be executing
we could not be executing
you could not be executing
they could not be executing	I could not have executed
you could not have executed
she could not have executed
we could not have executed
you could not have executed
they could not have executed	I could not have been executing
you could not have been executing
she could not have been executing
we could not have been executing
you could not have been executing
they could not have been executing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I execute?
could you execute?
could she execute?
could we execute?
could you execute?
could they execute? 	could I be executing?
could you be executing?
could she be executing?
could we be executing?
could you be executing?
could they be executing? 	could I have executed?
could you have executed?
could she have executed?
could we have executed?
could you have executed?
could they have executed? 	could I have been executing?
could you have been executing?
could she have been executing?
could we have been executing?
could you have been executing?
could they have been executing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not execute?
could you not execute?
could she not execute?
could we not execute?
could you not execute?
could they not execute? 	could I not be executing?
could you not be executing?
could she not be executing?
could we not be executing?
could you not be executing?
could they not be executing? 	could I not have executed?
could you not have executed?
could she not have executed?
could we not have executed?
could you not have executed?
could they not have executed? 	could I not have been executing?
could you not have been executing?
could she not have been executing?
could we not have been executing?
could you not have been executing?
could they not have been executing?