纤维蛋白性心包炎特异性的体征是
A．心脏扩大
B．心音低钝
C．颈静脉怒张
D．肝大
E．心包摩擦音
参考答案：E
My brother usually ___ his classroom after school. But now he ___ basketball.
A．cleans; plays
B．is cleaning; plays
C．cleans; is playing
D．is cleaning; is playing
（）是保证食品安全的第一责任人。
A、食品生产者
B、各级政府
C、监管部门
D、食品销售者
