80107
Could the word いかに always be replaced by どんなに／いくら／どれだけ／どれほど／なんと in structures
like

  1. いかに～か
  2. いかに～ても／でも
  3. いかに～とも
  4. いかに～ことか

Basically, what I would like to know is if いかに and どんなに／いくら／どれだけ／どれほど／なんと are
considered synonyms or there is any difference.

Thank you so much in advance for your help!
CC BY-SA 4.0
2020-08-12T13:36:34.257
80100
2020-08-13T07:04:28.820
29677
question
grammar words synonyms
Synonyms of いかに
1.     * いかに [adj.] か "How [adj.] (it) is!" (exclamatory)  
= どんなに／どれだけ／どれほど／なんと

    * いかに [V] か "how to V"  
= どう／どのように／どうやって

  2.     * いかに [adj.] ても／でも "no matter how [adj.]"  
= どんなに／いくら／どれだけ／どれほど／どれくらい

    * いかに [V] ても "no matter how [V]"  
= どんなに／いくら／どれだけ／どれほど／どれくらい (how much)  
= どう／どのように／どうやって (in what manner)

  3. = #2 except verbs' conjugation (also often become volitional form "no matter how (it) _would/should_ [V]")
  4.     * いかに [adj./V] ことか "How [adj./V-ing] (it) is!" (explicitly exclamatory)  
= どんなに／どれだけ／どれほど／なんと  
(only such verbs that is semantically stative could be used)

Basically いか is an older word that has double face of "how much" and "what
manner/type". To make things more complex, it is often involved in idiomatic
or largely fixed expressions, which you have asked. There are only limited
forms how いか is employed today:

  * いかに: (degree) どんなに／いくら etc.; (manner) どう／どのように etc.
  * いかなる: どんな／どのような "what kind of"
  * いかが: どう "how about; what about; what like"
  * [いかん](https://japanesetest4you.com/flashcard/learn-jlpt-n1-grammar-%E3%81%84%E3%81%8B%E3%82%93%E3%81%A7%E3%81%AF-ikan-dewa/) (almost a particle; better see the link)
  * [いかんせん](https://dictionary.goo.ne.jp/word/%E5%A6%82%E4%BD%95%E3%81%9B%E3%82%93/) "unfortunately"
CC BY-SA 4.0
2020-08-13T07:04:28.820
80107
2020-08-13T07:04:28.820
7810
80100
answer