仅个体变元被量化的谓词称为（）
A.一阶谓词
B.原子公式
C.二阶谓词
D.全称量词
参考答案：A
The meeting was concerned _____reforms and everyone present was concerned _____their own
interests. [ ]
A. about; with
B. with; by
C. for; about
D. with; about
脑底动脉环在脑循环中起着非常重要的作用，能沟通脑前、后、左、右的血液供应，下列哪条动脉不参与脑底动脉环的组成（）
A.大脑前动脉
B.前交通动脉
C.颈内动脉
D.大脑后动脉
E.椎动脉
