The boss asked me to buy two ____ for his children.
A. pair of shoes
B. pairs of shoe
C. pairs of shoes
Xi'an is one of ____ capital ____ in China.
A. older, city
B. the older, city
C. the oldest, cities
I can't get on the bus, because there is _____ on it.
A. little room
B. no rooms
C. not any rooms
Look! There are some _____on the floor.
A. boxes
B. water
C. child
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