There used to stand a tower at the foot of the hill . (不用 would)
4、在句型 “It is time that …；It is about time that … ；It is high time that … ”后的从句中用一般过去时。在 would rather , would sooner , had rather , had sooner 后的从句中用一般过去时。
It is high time that we went to school .
I had rather you came next week .

二、学海导航
【学法指要】
Unit 7 句型与难点释疑
Lesson 25
1. I don\'t think these will be enough . 我认为这些还不够。
〖释疑〗注意陈述句以第一人称主语 I / we + don\'t think (expect , believe , guess , imagine , suppose) + that 从句时，反意疑问句与从句相一致 ， 用肯定式，因否定已前移。否则，主句是由其他人称作主语时，仍与主句相一致。例如：
I don\'t think these will be enough , won\'t they ?
We don\'t believe that she has her breakfast , does she ?
对比：we don\'t believe that she has had her breakfast , has she ?
He doesn\'t suppose you are a great success , does he ?
2. What can we do to make it look less ugly ? 我们能想个什么办法使它不那么难看呢 ？
〖释疑〗注意使用 make sb do , make oneself done , be made to do , make sth to do
They made us work all day and all night against the flood water . = We were made to work all … .
She raised her voice to make herself heard by all of the them .
He made a box to put his shoes in .
3. As long as that ? 要那么长的时间吗 ？= Will it take as long as that ?
〖释疑〗as long as 长达……之久。
It took as long as eight years to repair the old temple .
It took them as long as three years to find out the cause of the plane crash .
It took this tennis player as long as four hours to win the championship .
另外注意 as long as = so long as = if “只要”引起条件状语从句，句中用现在时代替将来时。
You can smoke as long as you are not afraid of breaking the rules .
Lesson 26
1. Piles of stones lie in a corner of the courtyard , waiting to be replaced . 院子的角落里放着一堆一堆的石头，准备作更换之用。
〖释疑〗句中的 waiting to be replaced 是现在分词短语作伴随状语。这时可以变为并列谓语动词的句子或者非限制性定语从句。如上面的分词短语可换为：
Piles of stones are in a corner of the courtyard , and are waiting to be replaced .
Piles of stones are in a corner of the courtyard , which were waiting to be replaced .
Many people stood along the river bank watching the boat race . = Many people stood along the river bank and watched the boat race .
2. As the sun sinks lower , shadows spread across the courtyard . 随着夕阳西下，院内的阴影扩展开来。
〖释疑〗as 作连词引导的时间状语从句含有“当……的时候；一边……一边”。 when常含有“突然……”。while 常含有“对比”。
As one grows older , one becomes more experienced .
We were walking along the street when we heard “Help ! Help !”.
He was doing some reading while I was doing some washing .
3. To make things worse , many of the men have gone off to cities in search of higher pay , leaving women from nearby villages to carry on with the work . 更糟糕的是，很多男子去城里谋求较高工资的工作，因此，只有让附近村庄里的妇女来从事这一修复工作。
〖释疑〗to make things worse “使情况更糟糕的是”。
leaving women … 是现在分词短语作结果状语。