问题
选择题
It is said that potato chips ____________ by mistake about a hundred years ago.
A．invent
B．invented
C．are invented
D．were invented
答案
答案：D
考察时态及语态。句意；据说炸薯片是100年前错误的被发明的。结合语境可知本句描述的是过去的状态，故用一般过去时态。句子主语是动作对象，故用被动语态。选D。