键入文字 1表语从句一 定义： The problem is puzzling.主语 连系动词 形容词 作表语The problem is when we can get a pay rise.主语 连系动词 一个句子作表语-表语从句例句：He has become a teacher.He has become what he wanted to be ten years ago.She has remained there for an hour.She has remained where I stood yesterday for an hour.His suggestion is good.His suggestion is that we should stay calm.系动词有：look， be， remain， become， keep 等。考点：A 表语从句一定要用陈述语序。False: The question is when can he arrive at the hotel.Right: The question is when he can arrive at the hotel.B 不可以用 if，而用 whether 连接表语从句(as if 例外） 。引导宾语从句时可以互换 if/whether 引导 表语从句，主语从句，同位语从句 时要用 whetherFalse: The question is if the enemy is marching towards us.Right: The question is whether the enemy is marching towards us.Right: It looked as if he had understood this question.C that 在表语从句中不可以省掉。D “That is why.”是常用句型， 意为“这就是的原因/因此” ， 又如：That is why you see this old woman before you know, Jeanne. 珍妮， 这就是现在这个老太婆出现在你面前的原因。键入文字 2That is why I came. 这就是我来的原因。辨析 1：“That is why.” 与“That is the reason why.”：从语法结构上讲， “That is the reason why.”中 why 引导的是个定语从句， 将其中的 the reason 去掉则与“That is why.”结构一样， 例如： That is (the reason) why I cannot agree. 这就是我不能同意的理由。:辨析 2 “That is because.” 意为 “这就是为什么/ 因为” 。“That is because.”与“That is why.”之间的不同在于“That is because.”指原因或理由， “That is why.”则指由于各种原因所造成的后果， 例如： He did not see the film last night. That is because he had to help his little sister with her homework.昨天晚上他没有去看电影， 那是因为他得帮助他的妹妹做作业。(第一句话说明结果， 第二句话说明原因)He had seen the film before. That is why he did not see it last night.他以前曾看过那部电影， 因此他昨天晚上没有去看。( 第一句话说明原因， 第二句话说明结果 )