I can diphthongise you can diphthongise he can diphthongise we can diphthongise you can diphthongise they can diphthongise
V-ing form
I can be diphthongising you can be diphthongising he can be diphthongising we can be diphthongising you can be diphthongising they can be diphthongising
Perfect
I can have diphthongised you can have diphthongised he can have diphthongised we can have diphthongised you can have diphthongised they can have diphthongised
V-ing perfect
I can have been diphthongising you can have been diphthongising he can have been diphthongising we can have been diphthongising you can have been diphthongising they can have been diphthongising
Negation
Simple form
I cannot diphthongise you cannot diphthongise he cannot diphthongise we cannot diphthongise you cannot diphthongise they cannot diphthongise
V-ing form
I cannot be diphthongising you cannot be diphthongising he cannot be diphthongising we cannot be diphthongising you cannot be diphthongising they cannot be diphthongising
Perfect
I cannot have diphthongised you cannot have diphthongised he cannot have diphthongised we cannot have diphthongised you cannot have diphthongised they cannot have diphthongised
V-ing perfect
I cannot have been diphthongising you cannot have been diphthongising he cannot have been diphthongising we cannot have been diphthongising you cannot have been diphthongising they cannot have been diphthongising
Interrogative form
Simple form
can I diphthongise? can you diphthongise? can he diphthongise? can we diphthongise? can you diphthongise? can they diphthongise?
V-ing form
can I be diphthongising? can you be diphthongising? can he be diphthongising? can we be diphthongising? can you be diphthongising? can they be diphthongising?
Perfect
can I have diphthongised? can you have diphthongised? can he have diphthongised? can we have diphthongised? can you have diphthongised? can they have diphthongised?
V-ing perfect
can I have been diphthongising? can you have been diphthongising? can he have been diphthongising? can we have been diphthongising? can you have been diphthongising? can they have been diphthongising?
Interro-negative form
Simple form
can I not diphthongise? can you not diphthongise? can he not diphthongise? can we not diphthongise? can you not diphthongise? can they not diphthongise?
V-ing form
can I not be diphthongising? can you not be diphthongising? can he not be diphthongising? can we not be diphthongising? can you not be diphthongising? can they not be diphthongising?
Perfect
can I not have diphthongised? can you not have diphthongised? can he not have diphthongised? can we not have diphthongised? can you not have diphthongised? can they not have diphthongised?
V-ing perfect
can I not have been diphthongising? can you not have been diphthongising? can he not have been diphthongising? can we not have been diphthongising? can you not have been diphthongising? can they not have been diphthongising?