1. --Shall I lock the lab before I go home?
-- . I'll check it myself later.
A. Go ahead B. No problem C. No hurry D. Don’t bother
2. The World Expo is like great stage for cultural exchange, bringing people into closer contact with _____ rest of the world.
A. a; 不填 B. the; 不填 C. a; the D. the; the
