Questions 19 to 21 are based on the conversation you have just heard.

A．How many native speakers it had in Shakespeare’s time.
B．The number of people with an adequate working knowledge of it.
C．The situations where a common language is needed.
D．The purposes for people to learn a second language.

A．He does not have a good hearing.
B．He has been driving madly for a year.
C．He never takes what she says seriously.
D．He is always impatient with her.