按照约束性不同，标准可分为强制性标准和（)。

Hamburg originally is__________.

A. a kind of food

B. a round piece of beef

C. a city in Germany

D. the name of a village

Hamburg originally is __________.

A) a kind of food

B) a round piece of beef

C) a city in Germany

D) the name of a village

Hamburg is______.

A．a kind of food

B．a round piece of beef

C．the name of a village

D．a city in Germany

The hamburger, as a kind of popular American fast food,______.

A．has a history of over one hundred years

B．was brought to Europe in the 1850s

C．is usually eaten with the hot dog

D．is better served in Hamburg

The hamburger, as a kind of popular American fast food,

A．has a history of over one hundred years

B．was brought to Europe in the 1850s

C．is usually eaten with the hot dog

D．is better served in Hamburg

The hamburger, as a kind of popular American fast food,______.

A．has a history of over one hundred years

B．was brought to Europe in the 1850s

C．is usually eaten with the hot dog

D．is better served in Hamburg

The hamburger, as a kind of popular American fast food, _________.

[A] has a history of over one hundred years

[ B ] was brought to Europe in the l850s

[ C]is usually eaten with the hot dog

[ D]is better served in Hamburg

A．Generalization

B．Specialization

C．Extension

D．Specification

A、blues

B、jazz

C、rock and roll

D、folk