2 I_t_i_s_b_e__li_e_v_e_d__th__a_t__(人们相信)we should eat more vegetable and do more exercise.
【Pay attention to that, whether/if,what, 】 1. that 在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。 2. whether/if "是否" 在主语句中不做成分， 不能省略，放句首只能用whether, 不能用if. 3.what引导的主语从句除了起到引导从句的 作用外，还要承担具体的意义，what还会作 句子成分。
pronoun代词
5. That we will be late is certain.
6. It is certain that we shall be late. A sentence served as(充当) subject is called
Subject Clause.
【例句呈现】 观察下列例句，指出其中所包含的主语 从句及连接词: 1. What is needed for a long trip is careful preparation. 该句中主语从句是 _W__h_a_t_i_s_n_e_e_d_e_d_f_o_r_a_ _l_o_n_g_t_r_ip__，连接词为 _w_h_a_t_。
2. That Taylor Swift will come to my city
excites everybody. 该句中主语从句是 _T_h_a_t_T_a_y_l_o_r_S_w__if_t_will c_o_m__e_t_o_m__y_c_i_ty__，连接词为__th_a_t_。 3. Whether we will travel abroad or not
It is a surprise that… 令人惊奇的是… It is a fact that… 事实是 … It is a question that... 问题是...
It is a pity that 1. ______________(很遗憾)we lost the match.
It is a fact that 2. ______________(这是事实)he cheated in the exam.
2) It is + adj. +主语从句 如：It is clear/certain that… 很清楚/很肯定…
It is possible that... 很可能…… It is obvious that… 很明显… It is important that… 重要的是...
1. I_t _is__p_o_s_s_ib__le__th_a_t___(很可能)she will come back tomorrow. 2._I_t _is__o_b_v_io_u__s_t_h_a_t__(很明显)this measure is effective.
3) It + be +过去分词+主语从句 如：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……
1._I_t_i_s_r_e_p_o__rt_e_d__t_h_a_t__(据报道)20 people were killed in the accident.
order语序 陈述语序 indicative orderΒιβλιοθήκη conjunction 连接词
Conjunctions（连接词）
从属连词 连接代词 连接副词
that __无___词__义_____ whether/if ___"_是___否__"
__不___充当从句的任何成分
what, who, whom, which， whose,whatever,whoever... 充当从句的_主__语__, 表__语__,_宾__语__, 定语.
when, where, how, why...
充当从句的__状_语__
That Lady Gaga will come to our city next
Monday is certain. 该= I句t i中s c主er语ta从in 句tha是t _TL_ha_da_ty_L_Ga_ad_g_ya_G_w_ai_lgl_ac_o_wm_i_lel_tc_oo_m_ e otouroucritycintyexntexMt oMndonayda.y连接词为 t_h_a_t__。
Find out the subject(主语) in each sentence.
1. A book is on the desk
noun名词
2. Smoking is bad for you. verbal noun代词
3. To find a good job is my dream.
4 You are a student.
has not been decided. 该句中主语从句是 _W__h_e_t_h_e_r_w__e_w_i_l_l __ _tr_a_v_e_l_a_b_r_o_a_d__o_r_n_o_t_，连接词为 _w_h__et_h_e_r__。
Subject Clause
definition
定义
主语从句是在复合句中充当主语的 句子，起到主语的 作用。
高中语法主语从句优秀课件
Noun Clauses (名词性从句)
Object Clause （宾语从句）
Predicative Clause （表语从句）
Subject Clause (主语从句)
Appositive Clause （同位语从句）
Unit 4 Astronomy: the science of the stars
Formed Subject(形式主 语)
Subject clause
Real subject
总结:当一个句子主语过长时，用it作形式主 语(formed subject)，而把真正的主语或主 语从句后放句尾，避免 “头重脚轻”。
所以就构成了下面3种常用句型:
1) It is + n. +主语从句 如: It is a pity that... 遗憾的是……