1 . My   friend's   sister   is ____ office worker.

A．an

B．a

C．the

D．/

2 . You are not a child but ________ adult now.

A．a

B．an

C．the

3 . —Jim, there is ________ island near here, yes?
—Yes. ________ island is not big but beautiful so you can visit it in your free time.

A．a; The

B．an; The

C．an; An