单选题     Students all over the world have to work for their education. A college education in the United States is expensive. The costs are so high that most families begin to save for their children's education when their children are babies. Even so, many young people cannot afford to pay the expenses of full-time college work. They do not have enough money to pay for school costs. Tuition for attending the university, books for classes, and living expenses are high. There are other expenses such as chemistry and biology lab fees and special student activity fees for such things as parking permits and football tic, kets. The cost of college education increases every year.  However, classrooms are still crowded with students.  Some American students have scholarships or other support, but many do not.
    Students from other countries have money problems to overcome, too. Because students in most international programs need to have a sponsor, they work hard to earn scholarships or special loans. International students understand the value of going to school in another country. They also know that it is difficult. Yet just as Americans choose to attend American universities in spite of the difficulty, however, it is usually possible for students from abroad to work on university campuses to pay for some of the costs of their education. Some people believe that students value their education more if they work for it.

单选题     Tuition for attending the university in the United States is ______.

单选题     The word 'sponsor' in paragraph two means ______.

单选题     Students from other countries think that ______.

单选题     The second paragraph is mainly about ______.