急性汞中毒的主要临床表现()。
A.发热、口腔炎、消化道症状
B.贫血、腹痛、口腔炎
C.易兴奋、震颤、口腔炎
D.周围神经炎、皮疹、贫血
E.以上都不是
参考答案:A
By the time Jack returned home from America, his son __________ from college. [ ]
A. graduate
B. has graduated
C. had graduated
D. had been graduated
按照国家有关规定,不实行招标代理资格认定制度的机构是( )。
A.政府设立的集中采购机构
B.政府采购咨询、培训等相关专业服务机构
C.从事政府竞争性谈判业务机构
D.政府工程和服务的招标机构