I can diagnose you can diagnose he can diagnose we can diagnose you can diagnose they can diagnose
V-ing form
I can be diagnosing you can be diagnosing he can be diagnosing we can be diagnosing you can be diagnosing they can be diagnosing
Perfect
I can have diagnosed you can have diagnosed he can have diagnosed we can have diagnosed you can have diagnosed they can have diagnosed
V-ing perfect
I can have been diagnosing you can have been diagnosing he can have been diagnosing we can have been diagnosing you can have been diagnosing they can have been diagnosing
Negation
Simple form
I can't diagnose you can't diagnose he can't diagnose we can't diagnose you can't diagnose they can't diagnose
V-ing form
I can't be diagnosing you can't be diagnosing he can't be diagnosing we can't be diagnosing you can't be diagnosing they can't be diagnosing
Perfect
I can't have diagnosed you can't have diagnosed he can't have diagnosed we can't have diagnosed you can't have diagnosed they can't have diagnosed
V-ing perfect
I can't have been diagnosing you can't have been diagnosing he can't have been diagnosing we can't have been diagnosing you can't have been diagnosing they can't have been diagnosing
Interrogative form
Simple form
can I diagnose? can you diagnose? can he diagnose? can we diagnose? can you diagnose? can they diagnose?
V-ing form
can I be diagnosing? can you be diagnosing? can he be diagnosing? can we be diagnosing? can you be diagnosing? can they be diagnosing?
Perfect
can I have diagnosed? can you have diagnosed? can he have diagnosed? can we have diagnosed? can you have diagnosed? can they have diagnosed?
V-ing perfect
can I have been diagnosing? can you have been diagnosing? can he have been diagnosing? can we have been diagnosing? can you have been diagnosing? can they have been diagnosing?
Interro-negative form
Simple form
can't I diagnose? can't you diagnose? can't he diagnose? can't we diagnose? can't you diagnose? can't they diagnose?
V-ing form
can't I be diagnosing? can't you be diagnosing? can't he be diagnosing? can't we be diagnosing? can't you be diagnosing? can't they be diagnosing?
Perfect
can't I have diagnosed? can't you have diagnosed? can't he have diagnosed? can't we have diagnosed? can't you have diagnosed? can't they have diagnosed?
V-ing perfect
can't I have been diagnosing? can't you have been diagnosing? can't he have been diagnosing? can't we have been diagnosing? can't you have been diagnosing? can't they have been diagnosing?