alertness

名词

1. 1

   警觉、警戒、戒心

   The guards maintained a high level of alertness throughout the night.

   警卫整夜都保持高度警觉。

2. 2

   机敏、清醒、专注

   A short nap can improve your alertness for the rest of the day.

   小睡一下可以让你接下来一整天更清醒专注。