At 연세어학당, I learned a sentence with an implied subject, an object, a conjunction in the object, an adverb, and a verb. I will never forget it, because it was the first "big sentence" that I had learned in Korean, something more than just "어디 가세요" or "그것을 주세요". At any rate, it was important in my formation as a learner of the Korean language and thus Korean culture.
The point is, I have found that the sentence itself seems to be entirely untrue. Many people use their chopsticks to place hot ramen or other noodles onto a spoon to cool them off; to do this, they use their spoon in their left hand and their chopsticks in the right hand.
So I've been vexed by this for two decades because of that sentence in a textbook.
Is this particular manner outdated or not, or perhaps if the sentence were just for the use of textbook learning and not related to any true Korean custom or manner.
젓가락과 숟가락을 따로따로 써야합니다.
One must use the chopsticks and spoon separately.