I was annoyed with myself for having so quickly and mindlessly lost thirty dollars.

那么快愚蠢地丢了30美元，我很生自己的气。

I spent many hours mindlessly banging a tennis ball against the wall.

我花了好多个小时单调地对着墙打网球。

Don't exercise of mindlessly.

不要盲目地锻炼。

If you eat mindlessly, you will most likely overeat.

你如果盲目地吃，很可能会吃患上过多。

They mindlessly adopt someone else's thinking and language.

他们不加思索地接受别人的想法和语言。