强调句型的结构及其用法，强调句是人们为了表达自己的意愿或情感而使用的一种形式。英语常用的强调句结构是“It is(was)+被强调部分(主语、宾语或状语)+who(that)…”。
一般而言，被强调的部分指人时用who或that，其他情况一般用that。此强调结构用来强调除谓语外的多种句子成分。
在该结构中，It was…that(who)…为强调句的结构词，原则上说，若将其去掉，句子意思依然清楚，结构依然完整。可以据此区分强调句与主语从句和定语从句。
1.强调主语。
《剑桥雅思真题7》Test 4 Passage 2
It is this management mechanism that has allowed Alaska salmon stocks.
正是这种管理机制使得阿拉斯加鲑鱼的数量得以增加。
《剑桥雅思真题7》Test 1 Listening Section 3
It's what these individuals contribute to their places of work that makes you realize how important they are.
这些人对工作的贡献让你意识到他们的重要性。
《剑桥雅思真题7》Test B Section 3
However, it was his son Abraham Darby III who, in 1775, organized a meeting to plan the building of a bridge.
然而，是他的儿子亚伯拉罕·达比三世在1775年组织了一次会议，计划修建一座桥。
《剑桥雅思真题8》Test 3 Passage 1
It's a monster that takes up a whole room.
它是一个巨大的东西，占据了整个房间。
《剑桥雅思真题13》Test 4 Passage 2
It is an easily understood target that can help shape expectations and encourage action.
这是一个容易理解的目标，可以帮助形成预期并鼓励行动。
《剑桥雅思真题13》Test 2 Passage 2
It's a very simple and ancient molecule that has been co-opted for many different functions.
它是一种非常简单和古老的分子，已经被用于许多不同的功能。
《剑桥雅思真题6》Test 1 Passage 2
It is finished manufactured products that dominate the flow of trade.
在贸易流动中占主导地位的是制成品。
2.强调宾语。
《剑桥雅思真题4》Test 4 Passage 1
In Fosbury's case, it was the cushions that jumpers land on.
在福斯伯里的案例中，跳高者降落到的是垫子上。
3.强调状语。
《剑桥雅思真题6》Test 4 Listening Section 4
It was only in the nineteenth century that they disappeared from everywhere but India.
直到19世纪，它们才从印度以外的地方消失。
《剑桥雅思真题7》Test 2 Passage 1
It was only thirty years ago that the building industry felt confident enough to erect office blocks of steel and reinforced concrete that had more than a dozen floors.
只有在30年前，建筑业信心十足地建起了超过12层的钢筋混凝土办公大楼。
《剑桥雅思真题7》Test 4 Listening Section 4
It was in 1956 that the speed of the process was improved.
这一进程的速度是在1956年提高的。
《剑桥雅思真题8》Test 2 Passage 3
It is only when the faculty of smell is impaired for some reason that we begin to realise the essential role the sense of smell plays in our sense of well-being.
只有当嗅觉因某种原因受损时，我们才开始意识到嗅觉在我们的幸福感中所扮演的重要角色。
《剑桥雅思真题8》Test 3 Passage 2
It was only with the growth of paediatrics and psychology in the twentieth century that studies could be carried out on a more objective, if still not always very scientific, basis.
只有随着20世纪儿科和心理学的发展，研究才能在更客观的基础上进行，如果仍然不总是非常科学的话。
注意：not…until…句型的强调句。句型为：It is/ was not until+被强调部分+that+其他部分。此句型只用until，不用till。但如果不是强调句型，till, until可通用。
《剑桥雅思真题7》Test 2 Listening Section 3
It wasn't until the 1950s that the idea of an international treaty was proposed.
直到20世纪50年代，国际条约的想法才被提出。
《剑桥雅思真题9》Test 4 Passage 1
It was not until the spring of that year that she was introduced to Pierre Curie.
直到那年春天，她才被介绍给皮埃尔·居里。
《剑桥雅思真题12》Test 8 Passage 2
It was not until 1500 BC (however) that the first hollow glass container was made by covering a sand core with a layer of molten glass.
然而，直到公元前1500年，第一个中空玻璃容器是用一层熔融玻璃覆盖在砂芯上制成的。
4.强调从句。
《剑桥雅思真题4》Test 1 Listening Section 2
It was because of this fast-flowing water that this site was a natural place for manufacturing works.
正是因为水流湍急，这里才成为制造工厂的天然场所。
注意：被强调成分如果是主语或宾语，除that和who外，也可以用which。
《剑桥雅思真题7》Test 3 Passage 3
In Europe, it is undoubtedly the mountain ecosystem which has changed most rapidly and is most at risk.
在欧洲，无疑是山地生态系统变化最快、风险最大。
《剑桥雅思真题10》Test A Section 3
It is the wood of the kauri which is an important natural resource.
它是贝壳杉的木材，是一种重要的自然资源。
5.what引导主语从句表强调。
“what从句+be”强调句子的一部分，需要强调的内容在be后面。
《剑桥雅思真题7》Test 1 Passage 3
What is distinctive in the suggestopedic method is that they are devoted entirely to assisting recall.
暗示疗法的独特之处在于它们完全致力于帮助回忆。
《剑桥雅思真题7》Test 4 Passage 1
What they had failed to reckon with was what happened when the kite was opened.
他们没有想到的是风筝被打开时发生了什么事。
