()俗名“可可精”,是从古柯叶中分离出来的一种最主要的生物碱,属中枢神经兴奋剂,呈白色晶体状,无气味,味略苦而麻,兴奋作用强。
A.海洛因
B.可卡因
C.大麻
D.鸦片
参考答案:B
I feel it is you rather than the boy who________for being late for the speech. [ ]
A. is to blame
B. are to blame
C. is to be blamed
D. are to be blamed
MM理论是指()。
A.股利无关论
B.一鸟在手论
C.信息传播论
D.假设排除论