（）和（）同属于购买性支出。
参考答案：社会消费性支出、投资
His aunt wanted to have him _______ the radio, but he had had it ________ already.
A．repair, repair
B．to repair, repair
C．repaired, to repair
D．repair, repaired
人体循环系统结构中，不存在瓣膜的是（ ）
A．心房心室之间
B．动脉血管内
C．四肢静脉血管内
D．心室和动脉之间
