Thanks for all your replies above.
Using vedio in an EAP context especially before the class requires students to get preparation about a topic so that they can share their viewpoints with others in class. Students can watch the vedio repeatedly and give their responses, which save much time in class, compared to tradtional listening class.But time management is key to students. The three tools recommended cann’t monitor the number of students who finished or did’t finish the task. Maybe teachers can use other accesssing tools to check students’ performance.