Backward channel
[计] 反向信道
🧩 词语组成解析
🗣️ 情景例句
Going away to college for the first time
第一次离家上大学，
Work today, for you know not how much you may be hindered tomorrow.
今天有事今天做，明天可能事受阻。
It was necessary, therefore, to invent instruments that neither slumbered nor slept.
因此，有必要发明一种仪器，既不打盹儿，也不睡觉。