第一节 单项填空（共15小题；每小题1分，满分15分）
21. Every national flag gives _____ country it represents ____ unique identity.
A. a; an B. the; a C. the; an D. a; a
22. This is a new _____ to language teaching, which can stimulate students’ interest in learning the language.
A. approach B. means C. method D. way
23. She promised _____ he had enough money, she would marry him.
A. that B. that if C. whether D. if that
24. He was found _____ in front of the computer, ______ games.
A. to sit; to play B. seated; playing C. seating; playing D. sitting; played