Inthe1950sintheUSA,mostfamilieshadjustonephoneathome,a...
來源：國語幫 1.61W
問題詳情：
In the 1950s in the USA, most families had just one phone at home, and wireless phones ____ yet.
A. haven’t invented B. haven’t been invented
C. hadn’t invented D. hadn’t been invented
【回答】
D
知識點：動詞時態與語態
題型：選擇題
