1 . He is ________ excellent scientist in the world, who is ________ honour to his hometown.

A．a, a

B．an, an

C．a, /

D．the, the

2 . —It is terrible that I made ________ mistake. But I won’t make the same one for ________ second time.
—Never mind. Nobody is perfect.

A．a; a

B．a; the

C．the; the

D．a; /

3 . If you have _______ chance of studying abroad to research about the local customs and culture, I think living with a host family will be _______ smart choice.

A．a; a

B．the; the

C．the; a

D．a; the