察觉出

How did you spot those fifties were counterfeited?

你怎样觉出那些50元面值的纸币是伪造的?

I detected a faint note of weariness in his voice.

从他的声音中觉出一丝。

I can detect signs of improvement in your thinking.

可以觉出你思考题方面的进步。

I soon discerned that the man was lying.

很觉出这个人是在撒谎。