The number of reported crimes is increasing at an alarming rate.
报警案件的数量正在以惊人的速度增长。
The speed at which cities are growing in the less developed countries is alarming.
欠发达国家城市发展的.速度令人担忧。
The disease is spreading with alarming rapidity.
这种疾病正在以令人吃惊的速度蔓延。