通常情况下,成分以烷烃为主的石油称为()。
A、烷烃石油
B、环烃基石油
C、裂解石油
D、石蜡基石油
参考答案:D
---Do you have any news about Bob?
---Yeah. We ______ each other quite a lot recently.[ ]
A. have been seeing
B. had been seeing
C. see
D. have seen
振动压路机与静作用压路机相比具有()等特点。
A.压实深度大
B.密实度高
C.生产效率高
D.压实遍数多
E.灵活性好