I can communicate you can communicate he can communicate we can communicate you can communicate they can communicate
V-ing form
I can be communicating you can be communicating he can be communicating we can be communicating you can be communicating they can be communicating
Perfect
I can have communicated you can have communicated he can have communicated we can have communicated you can have communicated they can have communicated
V-ing perfect
I can have been communicating you can have been communicating he can have been communicating we can have been communicating you can have been communicating they can have been communicating
Negation
Simple form
I can't communicate you can't communicate he can't communicate we can't communicate you can't communicate they can't communicate
V-ing form
I can't be communicating you can't be communicating he can't be communicating we can't be communicating you can't be communicating they can't be communicating
Perfect
I can't have communicated you can't have communicated he can't have communicated we can't have communicated you can't have communicated they can't have communicated
V-ing perfect
I can't have been communicating you can't have been communicating he can't have been communicating we can't have been communicating you can't have been communicating they can't have been communicating
Interrogative form
Simple form
can I communicate? can you communicate? can he communicate? can we communicate? can you communicate? can they communicate?
V-ing form
can I be communicating? can you be communicating? can he be communicating? can we be communicating? can you be communicating? can they be communicating?
Perfect
can I have communicated? can you have communicated? can he have communicated? can we have communicated? can you have communicated? can they have communicated?
V-ing perfect
can I have been communicating? can you have been communicating? can he have been communicating? can we have been communicating? can you have been communicating? can they have been communicating?
Interro-negative form
Simple form
can't I communicate? can't you communicate? can't he communicate? can't we communicate? can't you communicate? can't they communicate?
V-ing form
can't I be communicating? can't you be communicating? can't he be communicating? can't we be communicating? can't you be communicating? can't they be communicating?
Perfect
can't I have communicated? can't you have communicated? can't he have communicated? can't we have communicated? can't you have communicated? can't they have communicated?
V-ing perfect
can't I have been communicating? can't you have been communicating? can't he have been communicating? can't we have been communicating? can't you have been communicating? can't they have been communicating?