As long as we continue to face him, keep a suitable expression on our face, and don’t do something blatant such as belt out a show tune, how will he know that we’re actually somewhere else entirely?

只要我们继续看着对方，脸上保持适当的表情，不要有太明显的过分表现如哼歌出生，对方怎能知道其实我们的心早已飞到别的地方去了？

youdao

He says it is difficult to know how the disease will evolve.

VOA: standard.2009.05.14

And he cannot know how what he leaves behind will be used in his absence.

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Girardi said he didn't know how long it will be until Jeter sees game action, but believes he will likely get some at-bats before taking the field.

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We will know how to unite, he said, as we have so many times in the past.

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