. The reason for all the changes being made _______to us yet.A．has not explained

题型：不详难度：来源：

. The reason for all the changes being made _______to us yet.

A．has not explained	B．has not been explained
C．did not explained	D．were not explained

答案

解析

考查时态。根据题中时间状语yet可知用现在完成时态，根据语境可知用被动形式。句意：正在作所有改变的原因还没有向我们解释。

举一反三

Hurry up, or the tickets ________out by the time we get there.

A．will have sold

B．will sell

C．have sold

D．will have been sold

题型：不详难度：| 查看答案

Sorry, these two tables are already ______. You may book the one over there.

A．preserved

B．deserved

C．observed

D．reserved

题型：不详难度：| 查看答案

．The moment I got home, I found I _______ my jacket on the playground.

A．had left

B．left

C．have left

D．was leaving

题型：不详难度：| 查看答案

．The news came as no surprise to me. I ______ for some time that I would fail in the exam.

A．had known

B．knew

C．have known

D．know

题型：不详难度：| 查看答案

Public attention at the moment is ______ on the problem of how to create
opportunities for the laid-off workers.

A．focused

B．paid

C．attracted

D．concerned

题型：不详难度：| 查看答案