A、By the introduction of her friend. B、By a phone book. C、By a "Tutor Wanted" notice. D、By an advertisement on the Internet. C

M: Where are you going, Catherine? Today is Saturday.
W: Saturday isn’t a holiday for me anymore. (19) I have to tutor for three hours every Saturday afternoon.
M: That’s great. I wish I could find a part-time job to make a little pocket money. How did you find this job?
W: (20) I saw a "Tutor Wanted" notice stuck on a light pole near the bus stop. I phoned the number and I got the job. It’s not too hard to find a part-time job these days. But Richard, studying should always come first. Do you think that you have enough time to handle a part-time job?
M: It’s hard to say. If I can get a job, I will try very hard to make good use of my time.
W: We do spend too much time hanging around and doing nothing. Richard, your English is perfect. Why don’t you find a job teaching English?
M: But I don’t have any teaching experience. Speaking and teaching are two different things.
W: I don’t have any experience either. People know the fact that we’re just students. But we are young and energetic, and the most important thing is that we don’t ask for as much pay as professional teachers do.
M: OK! Where should I start?
W: (21) You can post some notices on the community bulletin board and some other places. But remember; don’t post them on the wire poles because you’ll probably be fined for it.
M: Thank you for your advice, Catherine.
W: My pleasure. Good luck.
19. What do we learn about the woman?
20. How did the woman find the part-time job?
21. What does the woman suggest the man do when starting to find a job?