He could not tell whether the floor was wood or stone.

他分不清这地板是木头的还是石头的。

《柯林斯英汉双解大词典》

He wanted to chuckle, but he could not tell his mouth to do it.

他想笑，但他的嘴不听使唤。

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He concluded that he had beheld her before; where he could not tell.

他最后肯定他从前见过她；但是他说不出在哪儿见过她。

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The second particle was deflected almost not at all. But what he could tell from the fact that there was a second particle at all, and the fact that it was in this direction, is that in addition to his negative particle, he also, of course, had a positive particle that was within this stream of rays that were coming out.

粒子的强烈信号,有着强烈的对比,第二个粒子几乎，不发生偏转，他能判断这是，第二个粒子的原因是它在这个方向,所以在出射射线中,除了有带负电的粒子外。

麻省理工公开课 - 化学原理课程节选

He could not tell the time, relying on the sun's angle and his own instincts to know when to eat or sleep.

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The court heard the brothers' sale on 19 October had attracted 400 people but prosecutor Will Noble said he could not tell if the robbers were present.

BBC: Jail for violent robbery at brothers' Langford farm

He could add and subtract using his fingers, but he could not tell the time, he did not know the seasons and he could not understand directions.

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