I can round you can round he can round we can round you can round they can round
V-ing form
I can be rounding you can be rounding he can be rounding we can be rounding you can be rounding they can be rounding
Perfect
I can have rounded you can have rounded he can have rounded we can have rounded you can have rounded they can have rounded
V-ing perfect
I can have been rounding you can have been rounding he can have been rounding we can have been rounding you can have been rounding they can have been rounding
Negation
Simple form
I cannot round you cannot round he cannot round we cannot round you cannot round they cannot round
V-ing form
I cannot be rounding you cannot be rounding he cannot be rounding we cannot be rounding you cannot be rounding they cannot be rounding
Perfect
I cannot have rounded you cannot have rounded he cannot have rounded we cannot have rounded you cannot have rounded they cannot have rounded
V-ing perfect
I cannot have been rounding you cannot have been rounding he cannot have been rounding we cannot have been rounding you cannot have been rounding they cannot have been rounding
Interrogative form
Simple form
can I round? can you round? can he round? can we round? can you round? can they round?
V-ing form
can I be rounding? can you be rounding? can he be rounding? can we be rounding? can you be rounding? can they be rounding?
Perfect
can I have rounded? can you have rounded? can he have rounded? can we have rounded? can you have rounded? can they have rounded?
V-ing perfect
can I have been rounding? can you have been rounding? can he have been rounding? can we have been rounding? can you have been rounding? can they have been rounding?
Interro-negative form
Simple form
can I not round? can you not round? can he not round? can we not round? can you not round? can they not round?
V-ing form
can I not be rounding? can you not be rounding? can he not be rounding? can we not be rounding? can you not be rounding? can they not be rounding?
Perfect
can I not have rounded? can you not have rounded? can he not have rounded? can we not have rounded? can you not have rounded? can they not have rounded?
V-ing perfect
can I not have been rounding? can you not have been rounding? can he not have been rounding? can we not have been rounding? can you not have been rounding? can they not have been rounding?