______useful dictionary for beginners of English! Where did you get it?

A．How

B．What an

C．What a

D．How a

------_________useful advice he gave me! _________kind he is!

A．What, How

B．How, What

C．What a, How

D．What an, How

       useful invention(发明) the computer is!

A．What an

B．What a

C．How

D．How a

_________ useful advice she gave you ! You should listen to her.

A. How             B. How a              C. What              D. What a

     useful invention(发明) the computer is!

A. What a    B. What an    C. How a     D. How an