I can tiptoe you can tiptoe he can tiptoe we can tiptoe you can tiptoe they can tiptoe
V-ing form
I can be tiptoing you can be tiptoing he can be tiptoing we can be tiptoing you can be tiptoing they can be tiptoing
Perfect
I can have tiptoed you can have tiptoed he can have tiptoed we can have tiptoed you can have tiptoed they can have tiptoed
V-ing perfect
I can have been tiptoing you can have been tiptoing he can have been tiptoing we can have been tiptoing you can have been tiptoing they can have been tiptoing
Negation
Simple form
I cannot tiptoe you cannot tiptoe he cannot tiptoe we cannot tiptoe you cannot tiptoe they cannot tiptoe
V-ing form
I cannot be tiptoing you cannot be tiptoing he cannot be tiptoing we cannot be tiptoing you cannot be tiptoing they cannot be tiptoing
Perfect
I cannot have tiptoed you cannot have tiptoed he cannot have tiptoed we cannot have tiptoed you cannot have tiptoed they cannot have tiptoed
V-ing perfect
I cannot have been tiptoing you cannot have been tiptoing he cannot have been tiptoing we cannot have been tiptoing you cannot have been tiptoing they cannot have been tiptoing
Interrogative form
Simple form
can I tiptoe? can you tiptoe? can he tiptoe? can we tiptoe? can you tiptoe? can they tiptoe?
V-ing form
can I be tiptoing? can you be tiptoing? can he be tiptoing? can we be tiptoing? can you be tiptoing? can they be tiptoing?
Perfect
can I have tiptoed? can you have tiptoed? can he have tiptoed? can we have tiptoed? can you have tiptoed? can they have tiptoed?
V-ing perfect
can I have been tiptoing? can you have been tiptoing? can he have been tiptoing? can we have been tiptoing? can you have been tiptoing? can they have been tiptoing?
Interro-negative form
Simple form
can I not tiptoe? can you not tiptoe? can he not tiptoe? can we not tiptoe? can you not tiptoe? can they not tiptoe?
V-ing form
can I not be tiptoing? can you not be tiptoing? can he not be tiptoing? can we not be tiptoing? can you not be tiptoing? can they not be tiptoing?
Perfect
can I not have tiptoed? can you not have tiptoed? can he not have tiptoed? can we not have tiptoed? can you not have tiptoed? can they not have tiptoed?
V-ing perfect
can I not have been tiptoing? can you not have been tiptoing? can he not have been tiptoing? can we not have been tiptoing? can you not have been tiptoing? can they not have been tiptoing?