高一英语名词性从句中it作形式主语练习题20题

高一英语名词性从句中it作形式主语练习题20题
1
<背景文章>
In English grammar, the use of "it" as a formal subject in subject clauses is quite common. This construction helps to make sentences more clear and easier to understand. For example, "It is important that we study hard." In this sentence, "it" is a formal subject and "that we study hard" is the real subject. Another example is "It is obvious that he is talented." Here, again, "it" acts as a formal subject and "that he is talented" is the actual subject.
The use of "it" as a formal subject can also be found in other types of sentences. For instance, in questions like "Is it true that she won the prize?" and statements such as "It seems that they are having a good time."
This grammatical structure is important for students to master as it appears frequently in both written and spoken English. It allows for more complex ideas to be expressed in a more organized way.
Now let's look at some sentences and determine the correct use of "it" as a formal subject.
1. ___ is necessary that we arrive on time.
A. That
B. This
C. It
D. What
2. ___ is clear that he has made a mistake.
A. There
B. Here
C. It
D. Where
3. ___ seems that they are not interested.
A. This
B. That
C. It
D. What
4. ___ is important to study regularly.
A. That
B. This
C. It
D. What
5. ___ is obvious that she is very intelligent.
A. There
B. Here
C. It
D. Where
答案：1. C。

解析：在“It is necessary that...”这个句型中，“it”作形式主语，真正的主语是“that we arrive on time”。

2. C。

解析：“It is clear that...”是固定句型，“it”作形式主语，“that he has made a mistake”是真正的主语。

3. C。

解析：“It seems that...”是常见句型，“it”作形式主语，“that they are not interested”是真正的主语。

4. C。

解析：“It is important to do sth.”中“it”作形式主语，真正的主语是“to study regularly”。

5. C。

解析：“It is obvious that...”中“it”作形式主语，“that she is very intelligent”是真正的主语。

2
<背景文章>
It is important to understand the usage of "it" as a formal subject in object clauses. When we use "it" as a formal subject, it makes the sentence structure more clear and easier to understand. For example, "It is clear that he is a talented student." In this sentence, "it" is the formal subject and "that he is a talented student" is the real subject. Another example is "It is known to all that the earth is round." Here, "it" again acts as a formal subject and "that the earth is round" is the real subject.
The use of "it" as a formal subject in object clauses can help us express complex ideas in a more concise and organized way. It allows us to focus on the main content of the sentence without being distracted by a long or complicated subject. This construction is very common in both written and spoken English, so it is essential for students to master it.
Now let's look at some more examples. "It is believed that hard work leads to success." In this sentence, "it" is the formal subject and "that hard work leads to success" is the real subject. "It is said that she has a beautiful voice." Here, "it" is the formal subject and "that she has a beautiful voice" is the real subject.
As you can see, the use of "it" as a formal subject in object clauses is a powerful tool for expressing ideas clearly and effectively. By understanding this construction, you will be able to improve your English writing and speaking skills.
1. <问题6>
It is important that we ______ hard to achieve our goals.
A.study
B.studies
C.studying
D.to study
答案：A。

解析：“It is important that...”后面的从句要用虚拟语气，即谓语动词用“should + 动词原形”，should 可以省略。

所以这里用study。

2. <问题7>
It is known to all that the sun ______ in the east.
A.rise
B.rises
C.rising
D.to rise
答案：B。

解析：表示客观真理的句子，谓语动词用一般现在时，且主语是the sun，谓语动词用第三人称单数形式rises。

3. <问题8>
It is believed that honesty ______ the best policy.
A.be
B.is
C.are
D.were
答案：B。

解析：“honesty is the best policy”是一个常见的表达，这里“it is believed that...”后面的从句用一般现在时，honesty 是不可数名词，谓语动词用is。

4. <问题9>
It is said that he ______ a famous writer.
A.is
B.are
C.be
D.were
答案：A。

解析：“it is said that...”后面的从句用一般现在时，主语是he，谓语动词用is。

5. <问题10>
It is necessary that we ______ on time.
A.arrive
B.arrives
C.arriving
D.to arrive
答案：A。

解析：“It is necessary that...”后面的从句要用虚拟语气，即谓语动词用“should + 动词原形”，should 可以省略。

所以这里用arrive。

3
<背景文章>
It is a well-known fact that in English grammar, the use of “it” as a formal subject in a predicate clause can add clarity and elegance to a sentence. For example, “It is important that we study hard.” In this sentence, “it” is the formal subject and “that we study hard” is the real subject. This construction is often used to make a statement more indirect and less blunt. Another example could be “It is clear that she is talented.” Here again, “it” acts as a placeholder, allowing the real subject to be presented in a more structured way.
The use of “it” as a formal subject in predicate clauses can be a bit tricky for students to understand at first. However, with practice and careful analysis, it becomes easier to recognize and use correctly. For instance, consider the sentence “It is necessary that he arrives on time.” The structure
of this sentence helps to emphasize the importance of his timely arrival without making the statement too direct.
Understanding this grammatical construction can greatly enhance one's writing and speaking skills. It allows for more sophisticated and nuanced expressions. Moreover, it is frequently encountered in various forms of written and spoken English, so mastering it is essential for effective communication.>
11. “It is obvious _____ he is a good student.”
A. that
B. which
C. what
D. who
答案：A。

中文解析：在这个句子中，“it is obvious that”是一个固定用法，表示“很明显……”，后面接的是一个主语从句，“that”在主语从句中不充当任何成分，只起连接作用。

12. “It is certain _____ she will pass the exam.”
A. if
B. that
C. whether
D. when
答案：B。

中文解析：“it is certain that”是固定搭配，表示“肯定……”，后面接主语从句，“that”在从句中不充当成分，只起连接作用。

13. “It is true _____ he has worked hard.”
A. which
B. that
C. what
D. who
答案：B。

中文解析：“it is true that”是常见用法，“that”引导的是主语从句，在从句中不充当成分。

14. “It is important _____ we protect the environment.”
A. that
B. which
C. what
D. who
答案：A。

中文解析：“it is important that”后面接主语从句，表示“……很重要”，“that”在从句中起连接作用。

15. “It is clear _____ he is telling the truth.”
A. that
B. which
C. what
D. who
答案：A。

中文解析：“it is clear that”表示“很清楚……”，后面接主语从句，“that”在从句中不充当成分。

4
<背景文章>
Noun clauses are an important part of English grammar. One of the interesting uses of "it" is as a formal subject in appositive clauses. An appositive clause is a clause that explains or gives more information about a noun. For example, "The fact that he passed the exam is amazing." In this sentence, "The fact" is the noun and "that he passed the exam" is the appositive clause. "It" can be used as a formal subject in such sentences. For instance, "It is a fact that he passed the exam." Here, "it" takes the place of the appositive clause to make the sentence structure more balanced.
Appositive clauses with "it" as the formal subject can be quite useful in expressing complex ideas. Consider the sentence, "It is clear that she is talented." Here, "that she is talented" is the appositive clause explaining the idea of her talent. Another example is "It is known to all that the earth is round." In this case, "that the earth is round" is the appositive clause providing well-known information.
Understanding how "it" functions as a formal subject in appositive clauses can help students improve their writing and comprehension skills. It allows for more elegant and clear expression of ideas.
1. <问题16>
It is an important point that he is honest. The underlined part is an appositive clause that explains the noun “____”.
A. important point
B. he
C. honest
D. is
答案：A。

中文解析：这句话中“that he is honest”是同位语从句，解释说明名词“important point”。

2. <问题17>
It is known to everyone that she is a good singer. The appositive clause in this sentence is “____”.
A. It is known to everyone
B. she is a good singer
C. known to everyone
D. is a good singer
答案：B。

中文解析：这句话中“that she is a good singer”是同位语从句，是对“it is known to everyone”中的“it”进行解释说明。

3. <问题18>
It is a fact that they won the game. The noun explained by the appositive clause is “____”.
A. a fact
B. they
C. won
D. game
答案：A。

中文解析：“that they won the game”是同位语从句，解释说明名词“a fact”。

4. <问题19>
It is clear that he is intelligent. The appositive clause here is “____”.
A. It is clear
B. he is intelligent
C. clear
D. is intelligent
答案：B。

中文解析：“that he is intelligent”是同位语从句，解释说明“it is clear”中的“it”。

5. <问题20>
It is believed that the sun is the center of the solar system. The appositive clause in this sentence is “____”.
A. It is believed
B. the sun is the center of the solar system
C. believed
D. is the center of the solar system
答案：B。

中文解析：“that the sun is the center of the solar system”是同位语从句，解释说明“it is believed”中的“it”。