当轴承的转速较高、只承受轴向载荷时，应选用（）。
A.向心球轴承
B.推力球轴承
C.向心推力球轴承
D.调心轴承
参考答案：B
导致肺炎的非典型病原体是（）
A.肺炎链球菌
B.军团菌
C.葡萄球菌
D.肺炎克雷白杆菌
E.铜绿假单胞菌
The writer spent half his life _____ a _____ English novel. [ ]
A. finish to write; 500-thousands-word
B. finishing writing; 500-thousand-word
C. to finish to write; 500-thousands-word
D. to finish writing; 500-thousand-word
