Definition: showing clear thought and reason Level: C1
他太沮丧了，无法保持理性。
He was too upset to be ___rational.
教授对这个现象给出了理性的解释。
The professor gave a ___rational explanation for the phenomenon.
尽可能保持理性，你就能第一次通过驾驶考试。
Be as ___rational as you can and you will pass your driving test the first time.
