多层建筑施工，在计划安排上确须进行立体交叉作业时，应事先采取（）防护措施。
A.有效
B.防范
C.隔离
D.安全
参考答案：C
(2013·高考辽宁卷)Briggs will ________as general manager when Mitchell retires.
A．get away
B．take over
C．set off
D．run out
— What does the fresh juice contain?
— ________of the juice ________ orange. It's very pure.
A．Four-fifth; are
B．Four-fifths; are
C．Four-fifth; is
D．Four-fifths; is
