happy birthday to 謙謙
happy to 謙謙
adj prep L2
happy birthday to 謙謙 .
 WORD_BOUNDARY  WORD_BOUNDARY  WORD_BOUNDARY
h a p p y WORD_BOUNDARY b i r t h d a y WORD_BOUNDARY t o WORD_BOUNDARY 謙 謙 WORD_BOUNDARY . WORD_BOUNDARY