1. The education of _______young is always _______ hot and serious topic in modern society.
A. the; / B. a; the C. /; the D. the; a
2. Scientists are trying to develop a special material, _______ they will make use of in space.
A. it B. that C. what D. one
3. ---He suggests the number of cars should be limited to stop air pollution.
--- __________, the idea is not very practical.
A. Sounds good as it B. As it sounds good
C. As good it sounds D. Good as it sounds
