Question

By the time he was twelve, Edison ________ to make a living by himself . A．would begin B．ha.

By the time he was twelve, Edison ________ to make a living by himself . A．would begin B．has begun C．had begun D．was begun

Answer 1

C

时态题。By the time +过去时，主句谓语用过去完成时态 选C。 句意：到爱迪生十二岁时他已开始自己谋生了。