To elaborate when there is content and be concise when there is not, adapting the length of speech or writing to the substance available; a principle of efficient communication.
写文章也一样，要学会有话即长，无话即短，才能让读者更好地吸收信息。
When writing, it's the same principle: learn to elaborate when there's content and be brief when there isn't, so that readers can better absorb the information.
Next Idiom