*__It_i_s_a__p_i_ty__th_a_t__(很遗憾)we lost the match.
*__It_i_s_a__f_a_c_t _th_a_t_(这是事实)he cheated in the exam.
2) It is + adj. +从句 It’s certain that… 肯定… It is possible that... 很可能…… It is unlikely that... 不可能…… It is obvious that… 很明显… It is true/surprising/good/funny that。。。 It is necessary \important \natural\... that… sb+(should) +do…
2.连接副词when，where， how， why等。
Why they suddenly disappeared still remains a mystery. When they will set off is not decided. Where she is from is unknown. How we will paint the house has not been decided.
表语从句
The news that we won the game is exciting.
同位语从句
引导名词性从句的连接词可分为三类： 连接词：that, whether, if 连 接 代 词 ： what, whatever, who, whoever, whom, whomever，which ，whichever，whose. 连接副词：when, where, how, why
*_I_t_i_s_p_o_s_s_i_b_le__th__a_t _(很可能)she will come back tomorrow. *__It_i_s_o__b_v_io_u_s__th__a_t _(很明显)this measure is
effective.
3) It +不及物动词+从句
It happened that...
三．表语从句
表语从句在复合句中作表语的名词性从句，放在系动 词之后，一般结构是“主语＋连系动词＋表语从句”。 1.常用的句型：The reason why... is that… ，
It/This/That is because+原因...， That/This is why+结果... 1) He got up late this morning. This is why he was late for school. 2）He was late for school again. It was because he got up late this morning. 3) The reason why he is late for school is that he missed the early bus.
3. whether引导的表语从句。(不用if) The question is whether they will support the plan. 4. that引导 The trouble is that I have lost his address. 5.what 引导表从 The girl was not what she was ten years ago. He has become what he wanted to be ten years ago.
What is needed for success is your hard work.
Who will take part in the meeting has not been decided. Whoever breaks the law will be punished. Which student will win the first is uncertain.
I heard that he joined the army. (2) 由what, whether (if) 引导的宾语从句，例如：
She did not know what had happened. I wonder whether you can change this note for me. (3) 动词＋间接宾语＋宾语从句。例如： She told me that she would accept my invitation. 2. 作介词的宾语，例如： Our success depends upon how well we can cooperate with one another.
碰巧……
It occurred to me that…我突然想起…
*_I_t_h_a_p_p_e_n_e_d__t_h_a_t_(刚好)I came into the office at that time.
*_I_t _o_c_c_u_r_re_d__t_o_m__e_t_h_a_t_(我突然想起)I forget to sent the letter.
4. it 可以作为形式宾语 it 不仅可以作为形式主语，还可以作为形式宾语
而真正的宾语that 从句则放在句尾，特别是在带复 合宾语的句子中。 例如：
We thought it good news that the fog had finally gone.
主 语 +make/think/find/feel/take/consider +it( 形 宾 )+ 宾 补 （ n./adj. ） +that 从 句 /to do/doing
It is a pity/shame that... 遗憾的是…… It is a surprise that…令人惊奇的是… It is a fact that… …是事实 It is common knowledge that… …是常识 It is no wonder/no surprise that....
3. 作形容词或过去分词的宾语，例如：
I am afraid (that) I’ve made a mistake.
I am sure (that) he will win the game.
She was surprised/pleased that he had passed the exam.
3.从属连词：that， whether等. that 引导主语从句只起引导作用，本身无实际意 义，在主语从句中不充当任何成分，但不能省略。
That people cut down too many trees destroyed the balance of nature. Whether it will rain or not is not clear. It was not clear whether/if the solid shape would last.
6. 连接代词who，whom，whose，what，which， whoever，whatever，whichever连接副词 where，when， how，why The problem is who can replace her. The question is when he can arrive at the hotel.
It must be admitted that…必须承认……
It cannot be denied that… 不可否认……
It must be pointed out that…需指出的是……
___It_i_s_r_e_p_o_r_te_d__t_h_a_t __(据报道)20 people were
2. 放系动词be，look，seem，sound，appear等后面。 常构成It seems/sounds/looks as if.... At that time，it seemed as if I couldn't think of the right word. It sounds as if someone is knocking at the door.
7. 使用虚拟语气的表语从句
在表示建议、劝告、命令含义的名词后的表语从句，谓 语动词需用“should+动词原形” 表示，should可省略。 常见的词有：advice，suggestion，order，proposal， demand，request,等。
4) It + be +过去分词+从句
It is said that...
据说……
It is known to all that... 众所周知……
It is reported that... 据报道……
It is believed that...据信……;人们相信……
It is suggested that + (should）do... 建议……
*it为形式主语
2.That they should like each other is natural. _I_t _is__n_a_tu__ra_l_t_h_a_t_t_h_e_y_s_h_o_u__ld__li_k_e_e_a_c_h__o_th__er.
这样就构成了下面一些常用句型: 1) It is + n. +从句
1)W__h_at___you said yesterday is right. 2) __T_h_a_t _she is still alive is a good thing.
It is a good thing that she is still alive.
二．宾语从句
宾语从句就是在复合句中作宾语的名词性从句，通常放 在主句谓语动词 (及物动词) 或介词之后。 1. 作动词的宾语 (1) 由that引导的宾语从句(that 通常可以省略), 例如：