溶原性细菌是指()
A.带有毒性噬菌体的细菌
B.带有前噬菌体基因组的细菌
C.带有R因子的细菌
D.带有F因子的细菌
E.带有Coi因子的细菌
参考答案:B
My pen friend, Susan, wrote to me, _____ the idea that she would come to Changchun next week.[ ]
A. expressed
B. to express
C. expressing
D. express
管网气体灭火系统管道末端应采用防晃支架固定,支架与末端喷嘴间的距离不应大于500mm。()