Long since


This question is on the SAT OG book page 661 # 29
One bracket contains an error.

The dolls in the collection, [all] [more than] two hundred years old, had been [carefully] carved for children [long since] gone.

Why isn't [long since] wrong? <Second question deleted.>

Thanks in advance!
Last edited by a moderator:
  • Just to be clear, all the other ones are considered correct save for "more than?"

    Do you mean that all the others are considered correct? How is long since correct? And how do I distinguish it when its usage is being used incorrectly?

    Thanks in advance
    All the words/constructions in brackets seems fine to me, fabxx - "long since + past participle" is an idiom.