This invention relates to electrical signaling t systems and, more particularly, to radio receiving t systems wherein it is desired to use one of a e plurality of radio sets with a single antenna and i to automatically connect only one radio receiving set to the antenna at any one time. ...
I don't know___ they have passed the exam. A.whatB.ifC.whenD.where 试题答案 在线课程 B 解析试题分析: 句意:我不知道他们是否通过了考试?此题考查宾语从句if 是否的意思;根据句意,故选B。 考点:考查宾语从句。 练习册系列答案 黄冈经典
() 27. 一Tom!I looked for you eve- rywhere at the party last night.一Oh,I to the party. A. am invited B. was invited C. am not invited D. wasn't invited