副詞as, so, how, tooの後は形容詞+a[an]+名詞の語順が可能という話
まとめ:
○ This is too expensive a car for me.
○ This car is too expensive for me.
○ How beautiful a flower this is!
○ What a beautiful flower this is!
× How beautiful flowers these are!
○ What beautiful flowers these are!
○ I can’t buy so expensive a computer.
○ I can’t buy such an expensive computer.
× I can’t buy so expensive computers.
○ I can’t buy such expensive computers.
○ She is as beautiful an actress as ever lived.