First, log in on to the website.
(Before you write a question, you should enroll in the course. If you are individual participants who do not enroll at your universities, please refer to the notice titled "How can individual participants apply for the course?")
Second, click the "Courses" menu and then the lecture which you want to ask questions.
Third, click "Q & A" in each lecture.
Finally, write your questions by clicking "Add a new discussion topic".