活断层
参考答案：
是指目前正在活动着的断层，或是近期曾有过活动而不久的将来可能会重新活动的断层。
(2011·福建)—It's nice.Never before ________ such a special drink!
—I'm glad you like it.
A．I have had
B．I had
C．have I had
D．had I
在热环境中锻炼时，血管扩张使机体散热加强。
