有一个多项式为a8﹣a7b+a6b2﹣a5b3+…，按照此规律写下去，这个多项式的第八项是（ ）。
﹣ab7
That light rail transit line(轻轨), __ _in July 2009 and ___ in 2012, will be China’s longest light rail transit line in history.
A．starting, completing
B．started, to be completed
C．to start, completed
D．starting, completed
《素问·上古天真论》女子"筋骨坚，发长极，身体盛状"的年龄是（）
A.四七
B.五七
C.六七
D.三七
E.二七
