问题

ny years, people __ electricears However, making them has been more difficult than predicted

A:received
B:have received
C:had received
D:was receiving

正确答案是：

同类题型

Take things easy! The new secretary will relieve us _____some of the paper work[ ]

The young man，who by then admission to university，decided to do some part-time jobs to gain more practical experience

Noticing small changes early helps you _______ some big changes that are to come.

Yaomingissotallthathecanbe________inthecrowdeasily.

____ a new building _____ in your school last year