My father is _______. And we just had a party for his _______ birthday last weekend.
A. forty; fortiethB. forty; fortyC. fortieth; fortyD. fortieth; fortieth
一Excuse me, where can I exchange _______?
一There is a bank on the second floor.
A. booksB. foodC. moneyD. stamps
Basketball is so popular a game in the world that ______ people play it for fun and exercise.
A. million of B. millions of C. millions D. two millions of
Don't be afraid of asking for help ______it is needed.
A. when B. after C. 
although D. unless
I want to know______do to improve my English.
A. what I can B. what can I C. how I can D. how can I
It's important______the piano well.
A. of him to play B. for him to play
C. of him playing D. for him playing
