背靠背直流输电工程通常选择()。
A.较低的额定直流电压
B.较大的额定直流电流
C.较高的额定直流电压
D.较小的额定直流电流
参考答案:A, B
Though I am improving in my study,I still have a long way to go ________ some of my classmates.
A.to compare with
B.to compare to
C.comparing with
D.compared with
出口化妆品由产地检验机构实施检验()查验放行
A.进境口岸检验机构
B.产地检验机
C.出境口岸检验机构D.到达地检验机构