I can suckle you can suckle he can suckle we can suckle you can suckle they can suckle
V-ing form
I can be suckling you can be suckling he can be suckling we can be suckling you can be suckling they can be suckling
Perfect
I can have suckled you can have suckled he can have suckled we can have suckled you can have suckled they can have suckled
V-ing perfect
I can have been suckling you can have been suckling he can have been suckling we can have been suckling you can have been suckling they can have been suckling
Negation
Simple form
I can't suckle you can't suckle he can't suckle we can't suckle you can't suckle they can't suckle
V-ing form
I can't be suckling you can't be suckling he can't be suckling we can't be suckling you can't be suckling they can't be suckling
Perfect
I can't have suckled you can't have suckled he can't have suckled we can't have suckled you can't have suckled they can't have suckled
V-ing perfect
I can't have been suckling you can't have been suckling he can't have been suckling we can't have been suckling you can't have been suckling they can't have been suckling
Interrogative form
Simple form
can I suckle? can you suckle? can he suckle? can we suckle? can you suckle? can they suckle?
V-ing form
can I be suckling? can you be suckling? can he be suckling? can we be suckling? can you be suckling? can they be suckling?
Perfect
can I have suckled? can you have suckled? can he have suckled? can we have suckled? can you have suckled? can they have suckled?
V-ing perfect
can I have been suckling? can you have been suckling? can he have been suckling? can we have been suckling? can you have been suckling? can they have been suckling?
Interro-negative form
Simple form
can't I suckle? can't you suckle? can't he suckle? can't we suckle? can't you suckle? can't they suckle?
V-ing form
can't I be suckling? can't you be suckling? can't he be suckling? can't we be suckling? can't you be suckling? can't they be suckling?
Perfect
can't I have suckled? can't you have suckled? can't he have suckled? can't we have suckled? can't you have suckled? can't they have suckled?
V-ing perfect
can't I have been suckling? can't you have been suckling? can't he have been suckling? can't we have been suckling? can't you have been suckling? can't they have been suckling?