1. His behavior has become increasingly erratic since he started taking medication.
自从他开始服药后，他的行为变得越来越不稳定。

2. The stock market's erratic fluctuations have made investors extremely cautious.
股市的不稳定波动使得投资者异常谨慎。

3. The erratic weather patterns have disrupted agricultural activities in the region.
不规律的天气模式打乱了该地区的农业活动。