bi1 bi1 but1 but1
bi1 bi1 but1 but1
on on on on
bi1 bi1 but1 but1 .
p i˥ WORD_BOUNDARY p i˥ WORD_BOUNDARY p u˥ t WORD_BOUNDARY p u˥ t WORD_BOUNDARY
b i 1 WORD_BOUNDARY b i 1 WORD_BOUNDARY b u t 1 WORD_BOUNDARY b u t 1 WORD_BOUNDARY . WORD_BOUNDARY