468是4的（）倍，是3的（）倍。

在网络层来看，城域网提供的主要业务有（）和（）两种。

重楼的别名是（）

A.栝楼

B.莎草根

C.蚤休

D.仙灵脾

E.淡大芸

Use your head, _______ you’ll work out the problem.

A．so

B．or

C．for

D．and

This problem is ______ difficult __________.

A．so; that few of us can do

B．so; that few of us can do it

C．too; for anyone of us to do

D．too; for anyone of us to do it

评定饲料营养价值有哪几种方法？