wan wan baibai wan wan
wan wan baibai wan wan .
w a n WORD_BOUNDARY w a n WORD_BOUNDARY b a i b a i WORD_BOUNDARY w a n WORD_BOUNDARY w a n WORD_BOUNDARY
w a n WORD_BOUNDARY w a n WORD_BOUNDARY b a i b a i WORD_BOUNDARY w a n WORD_BOUNDARY w a n WORD_BOUNDARY