Who plays computer games？
A. Children.
B. Young men.
C. Old people.
D. All of above.
A．againstB．withC．toD．on
A. against
B. with
C. to
D. on
In what way is the market very real for each person or business who is making and selling
A. It tells you what to produce.
B. It tells you how to grow tomatoes.
C. It provides you with everything you need.
D. It helps you save money.
A．oneB．aC．otherD．another
A. one
B. a
C. other
D. another
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