Now listen to the following recording and answer questions 20 to 22
20
A.It helps them digest the food better as children.
B.It only relates to the politeness of eating.
C.It helps them better smell the food.
D.It makes them chewing faster and more carefully.
21
A.When you breathe in, airflow blocks the food particles from entering the lungs.
B.When you breathe out, airflow delivers the food particles to the lungs.
C.When you breathe in, airflow delivers the food particles to the nasal cavity.
D.When you breathe out, airflow blocks the food particles from entering the nasal cavity.
22
A.Keep one's mouth shut.
B.Wolf down the food.
C.Breathe slowly when eating.
D.Chew carefully when eating.