1. Some people are still in ____ habit of writing silly things in ____ public places.
A. the; the /
C. the; / the
2. As we know, ____ knowledge is a must in ____ international trade today.
A. a; / B. the; an
C. the; the D. /;the
3. She is ____ newcomer to ____ chemistry but she has already made some important discoveries.
A. the; the B. the; /
C. a; / D. a; the
4. The boy led the blind man by ____ arm to cross ____ street.
A. an; the B. the; the
C. the ; a D. an; a
5. Sometimes ____ weak can defeat ____ strong.
A. /; / B. the; the
C. the; a D. /; the