be short of 就是“……的縮寫”
如：BB is short of Blackboard
還有另一種形式be short for
如：Blackboard is short for BB
2 有“缺少……”之意
We're short of cash.
我們的資金不足
1.be short of 缺乏（反義詞組：be rich in）she is short of food.
2.的縮寫Phone is short of telephone.
be known as 意思是:作為.而出名,它的后面可以跟表示某種職業(yè)或某物的名詞.例如：
Lu Xun is known as a writer.
魯迅是作為作家而出名.
Zhou Jielun is known as a rap singer.
周杰倫是作為一個(gè)rap歌手而出名.