下列选项中,哪些会给高速公路上行车带来安全隐患?()
A.突然闯入的动物
B.超速行驶
C.紧急制动、违法停车
D.交通标志繁多,易使驾驶员眼花缭乱
参考答案:A, B, C
Last week the students did the experiment in order to_______ if iron rusts in dry air.
A.look for
B.look at
C.find out
D.find
再生障碍性贫血有何特点?