A: Hey, Matt. What are you wearing on your wrist(手腕)?
B: It's a Fitbit. I think it's a really useful invention.
A: Let me have a look.
B: It was invented in 2008 and it has become more and more popular since then.
A: It looks just like a watch.
B: A Fitbit is not just a watch.
A: Really? That's interesting.
B: Yes. It gives me helpful information. For example, it can count my steps and tell me if I exercise enough.
A: Cool!
B: It gives information about my sleep.
A: That's helpful!
B: I don't know. My mom gave it to me as my birthday gift.
A: Lucky you!
A. It can tell me about my health.
B. It must be very expensive.
C. When was it invented?
D. What else can a Fitbit do?
E. What is it used for?
