—Excuse me, do you know________ ?—Sure, there is a bookstore down the street near here.
A:where can I get some postcards
B:where I can get some postcards
C:how can I get some postcards
D:when I can get some postcards
Liu Wei met his old friends on ______ home yesterday.
一些列各组数中a,b,c 为边的三角形不是直角三角形的是( )
正常人的原尿与血液相比,主要区别是原尿中不含有( )