He wants to see ________ much stronger China within ________ rest of his life.

A．/; a

B．a; /

C．the; a

D．a; the

下列物理方法中，不能用于物质的分离或提纯的是（　　）

A．过滤

B．蒸馏

C．萃取

D．丁达尔效应