(\[*\d\d\d\d년\]*) ?[-:] ?→$1: 이렇게 했던거 같기도 하고 (\[*\d+년\]*) ?[-:] ?→$1: 이렇게 했던거 같기도 합니다………………(확신x
(\[*\d\d\d\d년\]*) ?[-:] ?
$1:
(\[*\d+년\]*) ?[-:] ?