I can strain you can strain he can strain we can strain you can strain they can strain
V-ing form
I can be straining you can be straining he can be straining we can be straining you can be straining they can be straining
Perfect
I can have strained you can have strained he can have strained we can have strained you can have strained they can have strained
V-ing perfect
I can have been straining you can have been straining he can have been straining we can have been straining you can have been straining they can have been straining
Negation
Simple form
I can't strain you can't strain he can't strain we can't strain you can't strain they can't strain
V-ing form
I can't be straining you can't be straining he can't be straining we can't be straining you can't be straining they can't be straining
Perfect
I can't have strained you can't have strained he can't have strained we can't have strained you can't have strained they can't have strained
V-ing perfect
I can't have been straining you can't have been straining he can't have been straining we can't have been straining you can't have been straining they can't have been straining
Interrogative form
Simple form
can I strain? can you strain? can he strain? can we strain? can you strain? can they strain?
V-ing form
can I be straining? can you be straining? can he be straining? can we be straining? can you be straining? can they be straining?
Perfect
can I have strained? can you have strained? can he have strained? can we have strained? can you have strained? can they have strained?
V-ing perfect
can I have been straining? can you have been straining? can he have been straining? can we have been straining? can you have been straining? can they have been straining?
Interro-negative form
Simple form
can't I strain? can't you strain? can't he strain? can't we strain? can't you strain? can't they strain?
V-ing form
can't I be straining? can't you be straining? can't he be straining? can't we be straining? can't you be straining? can't they be straining?
Perfect
can't I have strained? can't you have strained? can't he have strained? can't we have strained? can't you have strained? can't they have strained?
V-ing perfect
can't I have been straining? can't you have been straining? can't he have been straining? can't we have been straining? can't you have been straining? can't they have been straining?