仔细看右面方框中的内容，模仿model编对话。

—What's your favorite subject?  

—My favorite subject is Chinese.  

—Why do you like Chinese?  

—Because it's interesting.

1.______________________________________________________________________________ 

2.______________________________________________________________________________

3.______________________________________________________________________________

4.______________________________________________________________________________

5.______________________________________________________________________________

In (66) the strength of the carder signal is varied to represent binary 1 or 0. (67) is a system that can map a name to an address and conversely an address to an name. (68) is a three-way handshaking authentication protocol that it’s packets are encapsulated in the point-to-point protocol. (69) is an approach that enables an ATM Switch to behave like a LAN switch. (70) is an guided media which is made of glass or plastic and transmits signals in the form of light.

A．Coaxial cable

B．Optical fiber

C．Unshielded Twisted-pair Cable

D．Shielded Twisted-pair Cable