key link的用法和樣例：
例句
- The classroom instruction is the teaching profession center link.
課堂教學(xué)是教學(xué)工作的中心環(huán)節。 - "A science fiction cannot not be regarded as a mere entertainment, but in fact it tells the reader much more."
"科幻小說(shuō)不能簡(jiǎn)單地看成是供消遣的，而實(shí)際上它給讀者展示更深刻的內容。" - Iron and steel industry is the key link in a nation's economy.
鋼鐵工業(yè)是一個(gè)國家經(jīng)濟的主要環(huán)節。
