如果AB＞0，BC＞0，那么直线Ax-By-C=0不经过的象限是[ ]

A．第一象限

B．第二象限

C．第三象限

D．第四象限

— Have you ever been to Xiushui No.1 High School?  

— No. It is the first time that I ______ to Xiushui.  [ ]

A. come      

B. have come      

C. am coming    

D. came