As the summer time approaches, more and more commercials and advertisements can be seen on the mass media encouraging students to join English study tours abroad. The purpose of these tours is to provide students with an opportunity to learn English in a native speaking environment and use English in real situations. Parents always believe that their children will automatically speak good English after attending these study tours. However, for me, as an English major and former participant of many English study tours, I find these summer tours ineffective. Parents who send their children abroad for a summer to study English usually believe that the native speaking environment, including the courses, teachers, and host families, can help their children to learn English better. This might be true if the students really study hard and they really get an all-English environment. But the fact is that, most of the time, the tour part is more important than the study part. Although these tours take place in foreign countries, students are rarely exposed in an all-English environment. You will find that, in the morning classes, Taiwanese students would like to stick together and speak Chinese with each other, even though there are some students from other countries. In the afternoon, the students go on a sightseeing excursion  with their companions from Taiwan; they speak Chinese of course. In the evening, when students return to the host families, they would stay in their room and share the day with their roommate, another Taiwanese student. People who speak the same language with you is like a log in the ocean when living in a foreign country where you can not express yourself well, so that you would naturally stick with them. This is especially true with children. Another unrealistic expectation parents have for these tours is that the experience of living abroad can make their children more independent and mature. However, maturity does not come overnight. It takes time and practice. The most important of all is that they need a good  _ . None of these exist in the study tours. Which of the following is the most important thing for children who study in an English    environment according to the writer?
Host families. Hard work. Courses. Teachers.