I can flush you can flush she can flush we can flush you can flush they can flush
V-ing form
I can be flushing you can be flushing she can be flushing we can be flushing you can be flushing they can be flushing
Perfect
I can have flushed you can have flushed she can have flushed we can have flushed you can have flushed they can have flushed
V-ing perfect
I can have been flushing you can have been flushing she can have been flushing we can have been flushing you can have been flushing they can have been flushing
Negation
Simple form
I can't flush you can't flush she can't flush we can't flush you can't flush they can't flush
V-ing form
I can't be flushing you can't be flushing she can't be flushing we can't be flushing you can't be flushing they can't be flushing
Perfect
I can't have flushed you can't have flushed she can't have flushed we can't have flushed you can't have flushed they can't have flushed
V-ing perfect
I can't have been flushing you can't have been flushing she can't have been flushing we can't have been flushing you can't have been flushing they can't have been flushing
Interrogative form
Simple form
can I flush? can you flush? can she flush? can we flush? can you flush? can they flush?
V-ing form
can I be flushing? can you be flushing? can she be flushing? can we be flushing? can you be flushing? can they be flushing?
Perfect
can I have flushed? can you have flushed? can she have flushed? can we have flushed? can you have flushed? can they have flushed?
V-ing perfect
can I have been flushing? can you have been flushing? can she have been flushing? can we have been flushing? can you have been flushing? can they have been flushing?
Interro-negative form
Simple form
can't I flush? can't you flush? can't she flush? can't we flush? can't you flush? can't they flush?
V-ing form
can't I be flushing? can't you be flushing? can't she be flushing? can't we be flushing? can't you be flushing? can't they be flushing?
Perfect
can't I have flushed? can't you have flushed? can't she have flushed? can't we have flushed? can't you have flushed? can't they have flushed?
V-ing perfect
can't I have been flushing? can't you have been flushing? can't she have been flushing? can't we have been flushing? can't you have been flushing? can't they have been flushing?