I can change you can change he can change we can change you can change they can change
V-ing form
I can be changing you can be changing he can be changing we can be changing you can be changing they can be changing
Perfect
I can have changed you can have changed he can have changed we can have changed you can have changed they can have changed
V-ing perfect
I can have been changing you can have been changing he can have been changing we can have been changing you can have been changing they can have been changing
Negation
Simple form
I cannot change you cannot change he cannot change we cannot change you cannot change they cannot change
V-ing form
I cannot be changing you cannot be changing he cannot be changing we cannot be changing you cannot be changing they cannot be changing
Perfect
I cannot have changed you cannot have changed he cannot have changed we cannot have changed you cannot have changed they cannot have changed
V-ing perfect
I cannot have been changing you cannot have been changing he cannot have been changing we cannot have been changing you cannot have been changing they cannot have been changing
Interrogative form
Simple form
can I change? can you change? can he change? can we change? can you change? can they change?
V-ing form
can I be changing? can you be changing? can he be changing? can we be changing? can you be changing? can they be changing?
Perfect
can I have changed? can you have changed? can he have changed? can we have changed? can you have changed? can they have changed?
V-ing perfect
can I have been changing? can you have been changing? can he have been changing? can we have been changing? can you have been changing? can they have been changing?
Interro-negative form
Simple form
can I not change? can you not change? can he not change? can we not change? can you not change? can they not change?
V-ing form
can I not be changing? can you not be changing? can he not be changing? can we not be changing? can you not be changing? can they not be changing?
Perfect
can I not have changed? can you not have changed? can he not have changed? can we not have changed? can you not have changed? can they not have changed?
V-ing perfect
can I not have been changing? can you not have been changing? can he not have been changing? can we not have been changing? can you not have been changing? can they not have been changing?