Without noticing what I was doing, I took hold of the knob, and open comes the door!

我没有注意到我在做什么，我抓住门把手，门开了！

youdao

youdao

She swung around to him, spilling her tea without noticing it.

她急转过身来对着他，茶水洒了出来她都没注意到。

《柯林斯英汉双解大词典》

"I like the plants that people walk by every day without noticing, " she said.

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Mr Yanukovich, by contrast, seems to have waded across the Rubicon without noticing.

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Witnesses said the family moved slowly to begin with, but suddenly stopped in the middle of the road and apparently without noticing, stepped out in front of the three motorbikes.

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