unguarded
adj. 大意的；不小心的；无防备的
v. 使无防备（unguard 的过去分词）
例句
The museum was unguarded at night.
这个博物馆夜里无人看守。
《牛津词典》
It was something I'd let out in an unguarded moment.
那是我一不留神说漏了嘴的话。
I should not leave my briefcase and camera bag unguarded.
我不该留下我的皮箱和相机包无人看管。
《柯林斯英汉双解大词典》
