(¡¡¡¡)21. —What do you think of English?

—It's ____ useful subject.

A. an              B. a                  C. the                  D. /

(¡¡¡¡)22. —Emma, what's our first ____ in the afternoon?

—Art. And the second one is math.

A. name            B. lesson             C. number               D. term