题目内容：

阅读下面短文，按照句子结构的语法性和上下文连贯的要求，在空格处填入一个适当的词。

In American, most high school students take English, science, math and history.

In English 1., the students study grammar and read famous literature(文学名著). 2. science class, they study biology, chemistry or physics. History is 3. interesting to some students than other subjects 4. they learn about important events and places in the United States. Students take other courses, 5.. These are electives(选修课). 6. study music because they feel it is more enjoyable. Some 7. computer science because they think 8. is more practical.

In each class, teachers give students exams. Some exams are more difficult than 9., but a good student can always do 10..