Before people could write long time ago, they found other ways to tell the news. They built a fire to tell others what had happened. The smoke was a message, so others from far away places could see it and understand what had happened.
Then, people learned to write. Because some things needed to be kept secrets, they used numbers to mean letters or words. 1 means A, 2 means B, and 26 means Z.

【蝦皮:教育學程考題彙編(教】評論
X(A)物質X匱乏時,冰棒即是美食☆ →...