Question

Computers          in offices and homes since 1970s．

A．have been used

B．had been used

C．was

D．has been used

Answer 1

A

试题分析：句意：自从20世纪70年代开始，电脑被用在办公室和家里。因为与since连用时，前面的常用现在完成时，又因为Computers是复数，故选A。
点评：本题难度适中。对动词的考查是高考必考的内容，需要掌握它们的词义、用法、时态及语态等，对它们的考查在单选、完形及短文改错中经常出现，足以引起考生的重视。
即学即练：--- I hear you _______ at Smith’s.
--- Yes, I________there for about three months.
A．work; had been working 
B．worked; was working
C．are working; have been working 
D．worked; have worked
解析：C。句意：：--我听说你在史密斯那里工作。--是的，我一直在那里工作了3个月。根据句意选C。