If the answer below were correct, it would be also true when 'H-4' is substituted by 'F-1'. You would not consider an F-1 may take internship without CPT even it is part of course requirement, would you?
-F-1 with CPT can get paid, but H4 internship can not get paid. Also F1 requirement is different from H4 requirement for study, and thus you can not say something which works for H4 has to work for F1 also. For exmple, F1 student has to enroll full load courses, but H4 student does not need enroll full load course house.
Based on the H4 rule, the H4 hodler can study and get the professional training and even do some kind of volunteer (such as volunteer in hospital and charity work, etc.) as long as this kind of study or training is not considered as employment (e.g. not get paid, etc.).
