Read the text below and answer the questions that follow.
When is it time to stop studying?
It's 10 p.m. and six government employees are out checking the streets of Seoul, South Korea. But these are not police officers searching for teenagers who are behaving badly. Their mission is to find children who are still studying. And stop them.
Education in South Korea is very competitive. The aim of almost every schoolchild is to get into one of the country’s top universities. Only the students with the best grades get a place. The school day starts at 8 a.m. and the students finish studying somewhere between 10 p.m. and 1 a.m. at night. This is because many go to private academies called hagwon after school. Around 74 percent of all students attend a hagwon after their regular classes finish. A year’s course costs, on average, $2,600 per student. In Seoul, there are more private tutors than schoolteachers, and the most popular ones make millions of dollars a year from online and in-person classes. Most parents rely on private tutoring to get their children into a university.
With so much time spent in the classroom, all that students in South Korean high schools do is study and sleep. Some of them are so exhausted that they cannot stay awake the next day at school. It is a common sight to see a teacher explaining the lesson while a third of the students are asleep on their desks. The teachers don’t seem to mind. There are even special pillows for sale that fit over the arms of the chairs to make sleeping in class more comfortable. Ironically, the students spend class time sleeping so that they can stay up late studying that night.
The South Korean government has been aware of the faults in the system for some time, but now they have passed some reforms. Today, schoolteachers have to meet certain standards or take additional training courses.
However, the biggest challenge for the government is the hagwons. Hagwons have been banned from having classes after 10 p.m., which is why there are street patrols searching for children who are studying after that time. If they find any in class, the owner of the hagwon is punished and the students are sent home. It's a strange world, where some children have to be told to stop studying while others are reluctant to start.
Adapted from: LATHAM-KOENIG, Christina & OXENDEN, Clive. American English File 3 - Workbook. 2"“ edition. Oxford: OUP, 2014.
In the sentence “However, the biggest challenge for the government is the hagwons.” (last paragraph), the word HOWEVER could be correctly replaced in this context, without change of meaning, by: