I can recertify you can recertify he can recertify we can recertify you can recertify they can recertify
V-ing form
I can be recertifying you can be recertifying he can be recertifying we can be recertifying you can be recertifying they can be recertifying
Perfect
I can have recertified you can have recertified he can have recertified we can have recertified you can have recertified they can have recertified
V-ing perfect
I can have been recertifying you can have been recertifying he can have been recertifying we can have been recertifying you can have been recertifying they can have been recertifying
Negation
Simple form
I can't recertify you can't recertify he can't recertify we can't recertify you can't recertify they can't recertify
V-ing form
I can't be recertifying you can't be recertifying he can't be recertifying we can't be recertifying you can't be recertifying they can't be recertifying
Perfect
I can't have recertified you can't have recertified he can't have recertified we can't have recertified you can't have recertified they can't have recertified
V-ing perfect
I can't have been recertifying you can't have been recertifying he can't have been recertifying we can't have been recertifying you can't have been recertifying they can't have been recertifying
Interrogative form
Simple form
can I recertify? can you recertify? can he recertify? can we recertify? can you recertify? can they recertify?
V-ing form
can I be recertifying? can you be recertifying? can he be recertifying? can we be recertifying? can you be recertifying? can they be recertifying?
Perfect
can I have recertified? can you have recertified? can he have recertified? can we have recertified? can you have recertified? can they have recertified?
V-ing perfect
can I have been recertifying? can you have been recertifying? can he have been recertifying? can we have been recertifying? can you have been recertifying? can they have been recertifying?
Interro-negative form
Simple form
can't I recertify? can't you recertify? can't he recertify? can't we recertify? can't you recertify? can't they recertify?
V-ing form
can't I be recertifying? can't you be recertifying? can't he be recertifying? can't we be recertifying? can't you be recertifying? can't they be recertifying?
Perfect
can't I have recertified? can't you have recertified? can't he have recertified? can't we have recertified? can't you have recertified? can't they have recertified?
V-ing perfect
can't I have been recertifying? can't you have been recertifying? can't he have been recertifying? can't we have been recertifying? can't you have been recertifying? can't they have been recertifying?