【题目】The frequency of airline crashes is basically ______, but they do sometimes come in bunches.
A. random B. alarming C. countless D. steady
在线课程【答案】A
【解析】
考查形容词。A. random任意的；B. alarming令人担忧的；C. countless无数的；D. steady稳定的。句意：飞机失事的频率基本上是随机的，但有时确实是成群结队的。结合句意可知答案为A。