건

'This one' - 것은 shortened

A contraction of 것은, 'the thing, as for it'. In speech it almost never stands alone: it arrives glued on as 이건, 그건, 저건, and seven of these eight lines are 이건. It can also follow a person's name to mean 'X's one'. The pair worth learning is 이게 (from 이것이), which just points at the thing as the subject, against 이건, which sets it up in contrast to something else.

Register: spoken contraction