compulsory

When I renewed my Japanese driving licence, the exquisitely polite staff shuttled me from eye test to photo booth to fee payment and then asked me to report to "lecture room 28". These "safety" lectures are compulsory for anyone who's had a traffic infraction in the previous five years.Inside I found a group of disconsolate-looking souls waiting for our punishment to begin. A smartly-dressed man walked in and told us our "lecture" would begin in 10 minutes and last two hours!