I can woof you can woof she can woof we can woof you can woof they can woof
V-ing form
I can be woofing you can be woofing she can be woofing we can be woofing you can be woofing they can be woofing
Perfect
I can have woofed you can have woofed she can have woofed we can have woofed you can have woofed they can have woofed
V-ing perfect
I can have been woofing you can have been woofing she can have been woofing we can have been woofing you can have been woofing they can have been woofing
Negation
Simple form
I can't woof you can't woof she can't woof we can't woof you can't woof they can't woof
V-ing form
I can't be woofing you can't be woofing she can't be woofing we can't be woofing you can't be woofing they can't be woofing
Perfect
I can't have woofed you can't have woofed she can't have woofed we can't have woofed you can't have woofed they can't have woofed
V-ing perfect
I can't have been woofing you can't have been woofing she can't have been woofing we can't have been woofing you can't have been woofing they can't have been woofing
Interrogative form
Simple form
can I woof? can you woof? can she woof? can we woof? can you woof? can they woof?
V-ing form
can I be woofing? can you be woofing? can she be woofing? can we be woofing? can you be woofing? can they be woofing?
Perfect
can I have woofed? can you have woofed? can she have woofed? can we have woofed? can you have woofed? can they have woofed?
V-ing perfect
can I have been woofing? can you have been woofing? can she have been woofing? can we have been woofing? can you have been woofing? can they have been woofing?
Interro-negative form
Simple form
can't I woof? can't you woof? can't she woof? can't we woof? can't you woof? can't they woof?
V-ing form
can't I be woofing? can't you be woofing? can't she be woofing? can't we be woofing? can't you be woofing? can't they be woofing?
Perfect
can't I have woofed? can't you have woofed? can't she have woofed? can't we have woofed? can't you have woofed? can't they have woofed?
V-ing perfect
can't I have been woofing? can't you have been woofing? can't she have been woofing? can't we have been woofing? can't you have been woofing? can't they have been woofing?