继发于肾癌（）
A.精索静脉曲张
B.睾丸鞘膜积液
C.睾丸鞘膜积血
D.睾丸肿瘤
E.附睾炎
参考答案：A
He is often made ________ for twelve hours a day by the boss.[ ]
A. work
B.working
C. to work
D. to be working
下列不属于按照用途分的焊条是（）
A.碳钢焊条
B.合金焊条
C.碱性焊条
D.铸铁焊条
