I can validate you can validate he can validate we can validate you can validate they can validate
V-ing form
I can be validating you can be validating he can be validating we can be validating you can be validating they can be validating
Perfect
I can have validated you can have validated he can have validated we can have validated you can have validated they can have validated
V-ing perfect
I can have been validating you can have been validating he can have been validating we can have been validating you can have been validating they can have been validating
Negation
Simple form
I can't validate you can't validate he can't validate we can't validate you can't validate they can't validate
V-ing form
I can't be validating you can't be validating he can't be validating we can't be validating you can't be validating they can't be validating
Perfect
I can't have validated you can't have validated he can't have validated we can't have validated you can't have validated they can't have validated
V-ing perfect
I can't have been validating you can't have been validating he can't have been validating we can't have been validating you can't have been validating they can't have been validating
Interrogative form
Simple form
can I validate? can you validate? can he validate? can we validate? can you validate? can they validate?
V-ing form
can I be validating? can you be validating? can he be validating? can we be validating? can you be validating? can they be validating?
Perfect
can I have validated? can you have validated? can he have validated? can we have validated? can you have validated? can they have validated?
V-ing perfect
can I have been validating? can you have been validating? can he have been validating? can we have been validating? can you have been validating? can they have been validating?
Interro-negative form
Simple form
can't I validate? can't you validate? can't he validate? can't we validate? can't you validate? can't they validate?
V-ing form
can't I be validating? can't you be validating? can't he be validating? can't we be validating? can't you be validating? can't they be validating?
Perfect
can't I have validated? can't you have validated? can't he have validated? can't we have validated? can't you have validated? can't they have validated?
V-ing perfect
can't I have been validating? can't you have been validating? can't he have been validating? can't we have been validating? can't you have been validating? can't they have been validating?