在生态系统中，物质周转期是周转率的倒数。 ( )
参考答案：对
"五四"文学革命开展了对中国旧剧的讨论，翻译介绍欧美话剧，一些戏剧家提出了"（）"的口号（意为非职业戏剧、不以营利为目的）。
—Which driver was to blame?
—Why, _______！It was the child’s fault, clear and simple. He suddenly came out.between two parked cars.
A．both
B．each
C．either
D．neither
