I have some confusion about the grammar structure of 可以 Kěyǐ. I found in this website the basic usage is:
Subj. + 可以 + Verb + Obj.
But then I came across a dialogue where they put it after the verb:
Wǒ kàn yīgè yuè kěyǐ ma?
Can I read it for a month?
Question: Does this mean there is some flexibility about this order?