体育服务商品的供给
参考答案：
是指体育产业部门在一定时期内向社会提供的全部体育服务产品和体育服务商品的数量。
Everyone is supposed ______ a seat belt in the car. [ ]
A. wearing
B. to wear
C. to be worn
There is _______ egg in the cup. _______ egg is red. [ ]
A. a, An
B. an, A
C. an, The
D. a, The
