I can flow you can flow he can flow we can flow you can flow they can flow
V-ing form
I can be flowing you can be flowing he can be flowing we can be flowing you can be flowing they can be flowing
Perfect
I can have flowed you can have flowed he can have flowed we can have flowed you can have flowed they can have flowed
V-ing perfect
I can have been flowing you can have been flowing he can have been flowing we can have been flowing you can have been flowing they can have been flowing
Negation
Simple form
I cannot flow you cannot flow he cannot flow we cannot flow you cannot flow they cannot flow
V-ing form
I cannot be flowing you cannot be flowing he cannot be flowing we cannot be flowing you cannot be flowing they cannot be flowing
Perfect
I cannot have flowed you cannot have flowed he cannot have flowed we cannot have flowed you cannot have flowed they cannot have flowed
V-ing perfect
I cannot have been flowing you cannot have been flowing he cannot have been flowing we cannot have been flowing you cannot have been flowing they cannot have been flowing
Interrogative form
Simple form
can I flow? can you flow? can he flow? can we flow? can you flow? can they flow?
V-ing form
can I be flowing? can you be flowing? can he be flowing? can we be flowing? can you be flowing? can they be flowing?
Perfect
can I have flowed? can you have flowed? can he have flowed? can we have flowed? can you have flowed? can they have flowed?
V-ing perfect
can I have been flowing? can you have been flowing? can he have been flowing? can we have been flowing? can you have been flowing? can they have been flowing?
Interro-negative form
Simple form
can I not flow? can you not flow? can he not flow? can we not flow? can you not flow? can they not flow?
V-ing form
can I not be flowing? can you not be flowing? can he not be flowing? can we not be flowing? can you not be flowing? can they not be flowing?
Perfect
can I not have flowed? can you not have flowed? can he not have flowed? can we not have flowed? can you not have flowed? can they not have flowed?
V-ing perfect
can I not have been flowing? can you not have been flowing? can he not have been flowing? can we not have been flowing? can you not have been flowing? can they not have been flowing?