We live day by day, but in the great things, the time of days and weeks____ so small that a day

is unimportant.      [ ]

A. is            

B. are          

C. has been    

D. have been

为保证建筑制品、构配件等有关尺寸间的统一与协调，特规定了（）及相互之间的关系。

A.标志尺寸

B.定位尺寸

C.构造尺寸

D.实际尺寸

E.定形尺寸