By using a credit card you can ______.

A．"I think you need a good rest to relax yourself"
B．"I think you need something to cheer you up"
C．"I think you need some advice from your friends"
D．"I think you need to be more careful"

A．the importance of "guessing" in learning a foreign language
B．how to guess what one is going to talk about
C．some examples of correct guessing
D．how important it is to guess all the time