一、单项选择（共18分，每小题1分）从A、B、C、D四个选项中，选出可以填入空白处的最佳选项。
( ) 1. Please find out the _______ words and then put them in the blanks.
A. lost B. missing C. gone D. losing
( ) 2. Through the reform (改革), the economic situation of China _______ much better than it used to be.
A. turned into B. turned off C. turned to D. turned out
( ) 3. A graduation ceremony (仪式) is a custom ______ takes place _______ students graduate from a school.
A. which; when B. that; who C. which; whose D. that; which
( ) 4. —Do you know the old man to ______our head teacher is talking in the office?
