I can't understand as ... as structures in English. According to grammar books between the two as we should place an adjective, but I have seen several cases which there was something else. For example look at the following sentences and tell me which one is correct?
- I could not live in a city as crowded as Tokyo.
- I could not live in as crowded a city as Tokyo.
I think the first one is correct, but I also saw the second one in a book. If both are correct please let me know if there is any difference or not.