it seems likely that extra comforts we now enjoy have increased our happiness somewhat,but that deteriorating relationships have made us less happy.这个句子中的that deteriorating 为什么要加个that，去掉that不行吗？保留that和删除that有什么不一样，谢谢
it seems likely that extra comforts we now enjoy have increased our happiness somewhat,but that deteriorating relationships have made us less happy.这个句子中的that deteriorating 为什么要加个that，去掉that不行吗？保留that和删除that有什么不一样，谢谢
It seems likely that + 分句A ......,转折关系并列连词BUT 连接+另外一个分句B
其中分句A : 名词短语+定语从句+HAVE DONE 现在完成时形式构成 句子真正主语,前面IT 为分句A 的形式主语.
然而分句B :非谓语动词中的,动名词充当主语+HAVE DONE 现在完成时形式构成
分句A 与分句B 为并列关系, 不属于从属关系, 不属于前面形式主语IT 管辖的范围.
It seems that sb do sth = Sb seemed to do sth
It seems that he is lying=He seems to be lying
好象他在撒谎。(他似乎在撒谎)
seem 系动词 link-v.
1.好像; 仿佛
He certainly didn't seem to be a fool.
他当然不像是个傻瓜。
She seems a clever girl.
她好像是个聪明的姑娘。
The baby seems to be asleep.
那婴孩好像是睡着了。
He seemed disappointed when the man refused his request.
当那个人拒绝了他的要求时他看起来很失望。
He seems to think so.
他似乎认为如此。
The main streets seemed shining in the sun.
在阳光照射下, 大街似乎闪闪发光。
It seems that you are lying.
看来你在撒谎。
It seems to me that Peter has seen nothing of life.
在我看来, 彼得还不懂人情世故。
It seems as if you are the first one here.
看起来你是第一个来这儿的。
It seemed a pity to refuse.
拒绝似乎是可惜的。
There seems no need to go now.
好像没有必要现在就去。
There seems to be a misunderstanding between us.
我们之间好像有些误解。
2.（缓和语气）感到好像，觉得似乎
3.（表示不确切或客气）看来好像，似乎
(1)It seems likely that extra comforts we now enjoy （句子主语部分）（IT 做形式主语）（THAT 后面句子做句子真正主语）
句子意思(1)：我们现在享受额外舒服感好象是很可能
句子意思(2)：似乎很可能，我们当前享受的附加的舒适感
(2)have increased our happiness somewhat （句子谓语部分）
在某种程度上增加了我们幸福感
(3) but （that 建议删掉） deteriorating relationship have made us less happy （动名词短语做主语）（转折关系并列分句）（BUT 为转折关系并列连词，用来连接另外一个独立的分句，他们是一种并列关系，不属于一种从属关系，不属于第一个IT 形式主语对应真正主语范畴.）
但是使得关系渐渐变的恶化是我们不怎么快乐
追问汗……给我解释seem的意思干嘛
追答如果第二个THAT 也是属于形式主语IT 的所指代范畴的话，那么THAT 就是连词了，BUT 也是连词，一个分句不可以同时出现两个连词，与英语语法回发生矛盾和冲突，
分句（1）：It seems likely that extra comforts we now enjoy have increased our happiness somewhat
分句1句子语法结构：
主句语法结构：（主语+系动词+表语）
形式主语：It
真正主语：that extra comforts we now enjoy have increased our happiness somewhat
系动词：seems (为非BE 形式的连系动词，这样连系动词还有很多）
表语：likely （形容词做表语，意思，有可能的，有希望的，预料的）
从句语法结构：(名词+定语从句+谓语+宾语 ）
主语：the extra comforts （名词短语作宾语）
修饰主语的定语从句：(that /which we now enjoy )
谓语：have increased 助动词+动词过去分词充当句子复合谓语）
宾语：our happiness （名词短语作宾语）
状语：somewhat （程度副词做状语）
分句（2）：but deteriorating relationship have made us less happy
分句2语法结构：(名词+定语从句+谓语+宾语 ）
主语：deteriorating relationship (动名词短语作主语）
谓语：have made （助动词+动词过去分词充当句子复合谓语）
宾语：us （宾格代词充当宾语）
宾语补足语：less happy （形容词充当补足语）（另外happy比较级为happier)
分句（1）是个由It 做形式主语，that 从句子作主句主语的一个主语从句
分句（2）是一个有动名词短语做主语的一个简单句（时态为现在完成时态）
分句（1）与分句（2）是一种转折关系的并列句，连接并列句的连词为but .
全句话意思：我们目前享受的舒适和安逸，看来似乎可能增加我们幸福感，可是人与人之间关系的恶化却让我们变得不是那么幸福。
希望这样的解释能让你彻底明白并接受，谢谢！
结构是：it seems likely that A- - - , but B -- - - .
这是简单化的分析：
it seems likely that she will come, but to my mind there's every reason for her not to.
或者这样改写你的句子：
Though it seems likely that extra comforts we now enjoy have increased our happiness somewhat, deteriorating relationships have made us less happy.-------这样就更能看出，那个that是多余的。
== it seems likely that extra comforts we now enjoy have increased our happiness somewhat, but deteriorating relationships have made us less happy追问
这应该是个平行结构，前面 it seems like that…… that..... 两个that是并列的，不过因为意思有转折关系，加个but
追答如果是平行结构的化话，後面部分就必须是but also likely that ——.
希望对你有所帮助追问
看了前面三位的分析，有的长篇大论，有的主观臆测，我看了大学句法的结构，虽然你的回答很短，但是觉得你才是最合适的最切题的回答，谢谢你！
追答谢谢，祝你英语更上一层楼
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