I can serve you can serve she can serve we can serve you can serve they can serve
V-ing form
I can be serving you can be serving she can be serving we can be serving you can be serving they can be serving
Perfect
I can have served you can have served she can have served we can have served you can have served they can have served
V-ing perfect
I can have been serving you can have been serving she can have been serving we can have been serving you can have been serving they can have been serving
Negation
Simple form
I can't serve you can't serve she can't serve we can't serve you can't serve they can't serve
V-ing form
I can't be serving you can't be serving she can't be serving we can't be serving you can't be serving they can't be serving
Perfect
I can't have served you can't have served she can't have served we can't have served you can't have served they can't have served
V-ing perfect
I can't have been serving you can't have been serving she can't have been serving we can't have been serving you can't have been serving they can't have been serving
Interrogative form
Simple form
can I serve? can you serve? can she serve? can we serve? can you serve? can they serve?
V-ing form
can I be serving? can you be serving? can she be serving? can we be serving? can you be serving? can they be serving?
Perfect
can I have served? can you have served? can she have served? can we have served? can you have served? can they have served?
V-ing perfect
can I have been serving? can you have been serving? can she have been serving? can we have been serving? can you have been serving? can they have been serving?
Interro-negative form
Simple form
can't I serve? can't you serve? can't she serve? can't we serve? can't you serve? can't they serve?
V-ing form
can't I be serving? can't you be serving? can't she be serving? can't we be serving? can't you be serving? can't they be serving?
Perfect
can't I have served? can't you have served? can't she have served? can't we have served? can't you have served? can't they have served?
V-ing perfect
can't I have been serving? can't you have been serving? can't she have been serving? can't we have been serving? can't you have been serving? can't they have been serving?