English verb conjugation
CAN EXECUTE

Regular verb: execute - executed - executed

Affirmation

Simple form	V-ing form
I can execute you can execute he can execute we can execute you can execute they can execute	I can be executing you can be executing he can be executing we can be executing you can be executing they can be executing
Perfect	V-ing perfect
I can have executed you can have executed he can have executed we can have executed you can have executed they can have executed	I can have been executing you can have been executing he can have been executing we can have been executing you can have been executing they can have been executing

Negation

Simple form	V-ing form
I cannot execute you cannot execute he cannot execute we cannot execute you cannot execute they cannot execute	I cannot be executing you cannot be executing he cannot be executing we cannot be executing you cannot be executing they cannot be executing
Perfect	V-ing perfect
I cannot have executed you cannot have executed he cannot have executed we cannot have executed you cannot have executed they cannot have executed	I cannot have been executing you cannot have been executing he cannot have been executing we cannot have been executing you cannot have been executing they cannot have been executing

Interrogative form

Simple form	V-ing form
can I execute? can you execute? can he execute? can we execute? can you execute? can they execute?	can I be executing? can you be executing? can he be executing? can we be executing? can you be executing? can they be executing?
Perfect	V-ing perfect
can I have executed? can you have executed? can he have executed? can we have executed? can you have executed? can they have executed?	can I have been executing? can you have been executing? can he have been executing? can we have been executing? can you have been executing? can they have been executing?

Interro-negative form

Simple form	V-ing form
can I not execute? can you not execute? can he not execute? can we not execute? can you not execute? can they not execute?	can I not be executing? can you not be executing? can he not be executing? can we not be executing? can you not be executing? can they not be executing?
Perfect	V-ing perfect
can I not have executed? can you not have executed? can he not have executed? can we not have executed? can you not have executed? can they not have executed?	can I not have been executing? can you not have been executing? can he not have been executing? can we not have been executing? can you not have been executing? can they not have been executing?