The students had to attend at least five lectures a week. 
Die Studenten mussten mindestens fünf Vorlesungen pro Woche besuchen. 
Los estudiantes tuvieron que asistir al menos a cinco conferencias por semana. 
Les étudiants devaient assister à au moins cinq conférences par semaine. 
Gli studenti dovevano frequentare almeno cinque lezioni a settimana. 
นักเรียนต้องเข้าร่วมอย่างน้อยห้าครั้งต่อสัปดาห์ 
Các sinh viên đã phải tham dự ít nhất năm bài giảng mỗi tuần. 
学生们每周至少要参加五场讲座。 學生們每周至少要參加五場講座。