Observe the sentence below and analyse the following statements:

“you could study German, for example, with Breaking Bad”.

I. ‘could’ could be replaced by ‘can’ without affecting the meaning.

II. The question form of the sentence is “Could you study German, for example, with Breaking Bad?”.

III. To form a negation, we should only insert the ‘don’t’ before ‘could’.

Which ones are INCORRECT?