高声谈笑 上教堂祷告 去郊游 回家
At first, I didn’t know what ____ Facebook was, and now I do know what it is. I have to say, it sounds like ____ huge waste of time.
A./; the
B./; a
C.the; a
D.a; the
塔板上鼓泡元件脱落和腐蚀的原因有哪些?