( )1. ________ brightly colored pills can be mistaken for sweets and they should be kept under ________lock and key.
A．the; the B．the；/ C．/；the D．/；/
( )2. Is this ________umbrella I chose just now?
A．a B．an C．the D．/
( )3. After he left ________ university，he turned________ doctor.
A．an; a B．a; a C．the；/ D．/; /
