2021届河北衡水高三英语新高考语法复习讲义考点（十四）从属连词that, whether与if引导的名词性从句

2021 届河北衡水高三英语新高考语法复习讲义 考点（十四）从属连词 that, whether 与 if 引导的名词性从句 课堂真题讲解 [全析考法] 单句语法填空/单句改错 1 ． It is possible ________ caffeine may cause birth defects ( 缺 陷 ) in humans, too. 2． She asked me________ I had returned the books to the library, and I admitted that I hadn't. 3． The most pleasant thing of the rainy season is________ one can be entirely free from dust. 4． The manager put forward a suggestion ________ we should have an assistant. There is too much work to do. 5 ． It is often the case________ anything is possible for those who hang on to hope. 6. After looking at the toy for some time, he turned around and found where his parents were missing.________________ 解析：that　分析句子结构可知，该句是一个主从复合句，it 作形式主语，that 从句为真正的主语。 解析：whether/if　句意：她问我是否已经把书还给图书馆了，我承认说我还 没有还。分析句子结构可知，空格处引导宾语从句，且在从句中不作任何成分，只起连接作用；又根据句意可知此处表示“是否”，故用 whether 或 if 引导宾语从句。 解析：that　句意：雨季最令人高兴的事情就是人们可以完全远离灰尘。分析 句子结构可知，本句包含一个表语从句，且表语从句中句子结构完整，故使 用 that 引导表语从句，that 在表语从句中不作句子成分，只起连接作用。 解析：that　句意：经理提出了一个建议，我们应该有一个助手。工作太多了。 分析句子结构可知，空处引导同位语从句，解释说明 suggestion 的具体内容， 故填 that。 解析：that　句意：通常情况下，对于那些坚持希望的人来说，一切皆有可能。 空处引导主语从句，从句中不缺少任何成分且意思完整，故使用 that 引导。 解析：where→that 或去掉 where　found 后是一个宾语从句，不缺少句子 成分且句意完整，所以不能用 where，应该用 that 引导，that 也可省略。 课后知识总结 [谨记规则] (一)that 引导的名词性从句 that 引导名词性从句时本身无意义，只起连接作用，也不在句中作任何成分。 它引导的名词性从句结构和意义都完整，往往用于陈述事实。引导主语从句、 表语从句和同位语从句时，that 不能省略。引导宾语从句时，在口语和非正 式文体中，that 可省略。但下列情况下，that 不可省略： 1．that 从句作介词的宾语； I don't know exactly where he lives, except that it's somewhere out in the wilds.他具体住在哪里我不是很清楚，只知道是远离城市的边远地区。2．that 引导的从句位于句首时； That the earth goes around the sun is known to us all. 众所周知，地球围着太阳转。 3．宾语从句前有插入语时； We hope, on the contrary, that he will stay at home with us.恰 恰 相 反 ， 我们希望他和我们待在家里。 4．动词后有多个 that 引导的宾语从句时，只有第一个 that 可省略，从第二 个从句开始 that 不可省略； He told me (that) he had to leave and that he would be back soon.他 告诉我他得离开并且很快就会回来。 5．it 作形式宾语时，that 引导的宾语从句中 that 往往不可省略。 He has made it clear that the meeting will not be postponed.他清楚地 表明会议不会被推迟。 (二)that 引导主语从句时可用 it 作形式主语的四大句式 1． It＋ be＋ 形 容 词 (necessary, right, likely, unlikely, wrong, important, certain, clear, obvious, strange, normal 等)＋that 从句 It isn't likely that I should accept such an offer as that. 我不可能接受像那样的帮助。 2．It＋be＋名词(短语)(a pity, a shame, good news, a fact, an honour, a wonder, no wonder 等)＋that 从句 It's no wonder that he didn't want to go.难怪他不想去。3 ． It ＋ be ＋ 过 去 分 词 (said, told, heard, reported, decided, suggested, advised, ordered, remembered, thought, considered, well known, announced 等)＋that 从句 It is decided that the meeting has been put off until next Monday.会 议被推迟到下周一已经定下来了。 [ 特 别 注 意 ] 　 在 “ It ＋ be ＋ suggested/advised/ordered/requested/insisted/required ...＋that 从句” 结构中，从句谓语应用“(should＋)动词原形”。 It is suggested that you (should) spend more time in studying English. 建议你花更多的时间学习英语。 4． It＋ 特 殊 动 词 或 短 语 (seem, appear, happen, matter, turn out, occur to, make no difference 等)＋that 从句 It suddenly occurred to her that Joe was afraid of being alone. 她突然想到乔害怕独自一个人待着。 (三)whether 与 if 的用法 1．用 whether 或 if 均可的情况 (1)whether 可引导各种名词性从句。引导大部分动词后的宾语从句时，两者 均可。 (2)it 作形式主语，且主语从句在句末时，两者均可引导主语从句。 It's uncertain whether/if he'll come this evening. 他今天晚上是否会来还不确定。 2．用 whether 而不用 if 的情况(1)主语从句和宾语从句置于句首时； Whether we can have clean drinking water lies in what effective measures will be taken by the government about water pollution.我们 能否有干净的饮用水取决于政府将采取什么样的有效措施处理水污染问题。 (2)引导表语从句和同位语从句时； The problem is whether the air pollution can be controlled.问题是空气 污染能否被控制住。 He asked me the question whether we should give money to the homeless.他问了我我们是否该给无家可归者钱的问题。 (3)引导介词的宾语从句时； It depends on whether we have enough time. 这取决于我们是否有充足的时间。 (4)引导词与 or not 连用时； I don't know whether or not the report is true. ＝I don't know whether the report is true or not. 我不知道这个报道是否是真的。 (5)引导词后接 to do 时； They don't know whether to go there. 他们不知道是否去那里。 (6)有些动词如 leave, put, discuss, decide 等后的宾语从句； We discussed whether we should hold a meeting. 我们讨论了我们是否应召开一个会议。(7)避免用 if 引导产生歧义。 Let me know whether you are coming to our party. 让我知道你是否来参加我们的宴会。