各类作业人员接受了相应的安全生产教育和岗位技能培训，即可上岗。
参考答案：错
The special medicine for the disease was difficult to find though ________
everywhere.
A．sought
B．having sought
C．being sought
D．having been sought
诊断丝虫病主要靠取外周血检查（）
A.杆状蚴
B.丝状蚴
C.微丝蚴
D.腊肠蚴
E.成虫
