过去将来时的典型例题解析

正如我们通常要在时间状语从句以及条件状语从句使用一般现在时代替一般将来时一样，如果在时间状语从句或条件状语从句中，因语义的需要而使过去将来时，那么应改用一般过去时。如：

他说要是第二天下雨他们就待在家里。

误：He said they would stay at home if it would rain the next day.

正：He said they would stay at home if it rained the next day.

另外，当by the time后接一个句子起将状语从句时，其后的从句用一般现在时代替一般将来时，用一般过去时代替过去将来时。如下面是北京卷的一道高考题：

When I talked with my grandma on the phone, she sounded weak, but by the time we ______ up, her voice had been full of life.

A. were hanging B. had hung C. hung D. would hang

分析：C。从逻辑上说，当我在电话里和奶奶聊天时，她的声音听起来很虚弱；但到我们要挂电话时，她的声音又充满朝气。从逻辑上说，应该是“奶奶的声音又充满朝气”在先，“我们挂断电话”在后，如果是反过来的话，那说话者就无法听知道“奶奶的声音又充满朝气”之回事了。所以“挂断电话”应用一般过去时。另外，由于by the time后接句子引导时间状语从句时，从句谓语通常要用一般现在时代替一般将来时，用一般过去时代替过去将来时，所以选项D不能选。

过去将来时典型考题：

1. Did you predict that many students ______ up for the dance competition?

A. would sign B. signed C. have signed D. had signed

分析：A。根据主句谓语动词predict（预计）的意思可知，从句应用过去将来时，即指预计将要发生某事。又如：

She predicted that the improvement would continue. 她预测情况将继续好转。

2. He didn’t sell half as many videos as he thought he ______.

A. had B. would C. was D. sold

分析：B。he would为he would sell之省略，为过去将来时，表示在当时看来将会出现的情况。句意为：他售出的录像带还不到他设想的一半。又如：

It’s curious (that) Billy hasn’t phoned when he promised he would. 比利答应要打电话来的，但一直没有打，这很反常。