耐热铸铁大多为单相铁素体基体的（）
A．灰口铸铁
B．可锻铸铁
C．球墨铸铁
D．蠕墨铸铁
参考答案：C
葡萄球菌肺炎
A．瘀点B．充血性皮疹C．瘀斑D．血肿E．小红痣
Jack asked John ______ when he met him in the street.
A．he was going where
B．where he was going
C．where was he going
D．was he going where
