标注坡度时，箭头应指向（）方向。
A、上坡
B、下坡
C、前方
D、根据需要确定
参考答案：B
Nowadays we are often filled with some apparently _______ suggestions made by so-called experts on
how to keep in good health. [ ]
A. appropriate
B. aggressive
C. concrete
D. contradictory
乙型肝炎传给婴儿的主要方式是：
A．粪-口传染B．注射血浆制品C．输血D．母婴垂直传播E．密切生活接触
