aa1 dat1 dat1 dat1 dat1 dat1
aa1
fil
aa1 dat1 dat1 dat1 dat1 dat1 .
a̞˥ WORD_BOUNDARY
a a 1 WORD_BOUNDARY d a t 1 WORD_BOUNDARY d a t 1 WORD_BOUNDARY d a t 1 WORD_BOUNDARY d a t 1 WORD_BOUNDARY d a t 1 WORD_BOUNDARY . WORD_BOUNDARY