加强锅炉通风换气可消除()。
A.有毒气体
B.烟气
C.可燃气体
D.空气
参考答案:C
Jim sold most of his things.He has hardly___left in the house.
A.anything
B.everything
C.nothing
D.something
细菌质粒按生物学性状分为()
A.转移性质粒
B.耐药性质粒
C.Col质粒
D.Vi质粒
E.R质粒