I can sweeten you can sweeten she can sweeten we can sweeten you can sweeten they can sweeten
V-ing form
I can be sweetening you can be sweetening she can be sweetening we can be sweetening you can be sweetening they can be sweetening
Perfect
I can have sweetened you can have sweetened she can have sweetened we can have sweetened you can have sweetened they can have sweetened
V-ing perfect
I can have been sweetening you can have been sweetening she can have been sweetening we can have been sweetening you can have been sweetening they can have been sweetening
Negation
Simple form
I can't sweeten you can't sweeten she can't sweeten we can't sweeten you can't sweeten they can't sweeten
V-ing form
I can't be sweetening you can't be sweetening she can't be sweetening we can't be sweetening you can't be sweetening they can't be sweetening
Perfect
I can't have sweetened you can't have sweetened she can't have sweetened we can't have sweetened you can't have sweetened they can't have sweetened
V-ing perfect
I can't have been sweetening you can't have been sweetening she can't have been sweetening we can't have been sweetening you can't have been sweetening they can't have been sweetening
Interrogative form
Simple form
can I sweeten? can you sweeten? can she sweeten? can we sweeten? can you sweeten? can they sweeten?
V-ing form
can I be sweetening? can you be sweetening? can she be sweetening? can we be sweetening? can you be sweetening? can they be sweetening?
Perfect
can I have sweetened? can you have sweetened? can she have sweetened? can we have sweetened? can you have sweetened? can they have sweetened?
V-ing perfect
can I have been sweetening? can you have been sweetening? can she have been sweetening? can we have been sweetening? can you have been sweetening? can they have been sweetening?
Interro-negative form
Simple form
can't I sweeten? can't you sweeten? can't she sweeten? can't we sweeten? can't you sweeten? can't they sweeten?
V-ing form
can't I be sweetening? can't you be sweetening? can't she be sweetening? can't we be sweetening? can't you be sweetening? can't they be sweetening?
Perfect
can't I have sweetened? can't you have sweetened? can't she have sweetened? can't we have sweetened? can't you have sweetened? can't they have sweetened?
V-ing perfect
can't I have been sweetening? can't you have been sweetening? can't she have been sweetening? can't we have been sweetening? can't you have been sweetening? can't they have been sweetening?