چرا حرف اضافۀ بین اسم و صفت آومده؟ "a"

Question

This is too difficult a subject to even think about.

Answer 1

From: Practical English Usage by Michael Swan,

14 adjectives (3): position after as, how, so, too
    After as, how, so, too and this/that meaning so, adjectives go before a/an. This structure is common in a formal style.
    ​　　as/how/so/too/this/that + adjective + a/an + noun
    ​　　I have as good a voice as you.
    ​　　She is too polite a person to refuse.
    ​　　How good a pianist is he?
    ​　　I couldn't afford that big a car.
    ​　　It was so warm a day that I could hardly work.
    The structure is not possible without a/an.
    ​　　I like your country – it's so beautiful. (NOT I like your so beautiful country.)
    ​　　Those girls are too kind to refuse. (NOT They are too kind girls to refuse.)

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Comments

کامل ترین پاسخ رو دادی دوست عزیز. عالی بود. خیلی ممنونم از راهنمایی بی نظیرت. همیشه موفق باشی

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خواهش میکنم. لطف دارید. دست نویسنده کتاب درد نکنه.