“天下为家”取代“天下为公”开始于( )
A:夏朝
B:商朝
C:西周
D:东周
下面的句子弄乱了,请你重新排一排。
____一阵风吹过,树叶沙沙作响。
____我拾起一片仔细端详。
____我登高俯视,果然看见满山黄栌树。
____只见红叶像把小团扇似的,还散发着阵阵清香。
____树上长满了红叶。
① How much is it? ____ A. OK. Here you are.
② Can I try them on? ____ B. It's $89.
③ Is it too expensive? ____ C. It's very pretty.
④ How do you like this skirt? ____ D. Yes,it is.
You couldn't look up for anything on the I____.
如图,菱形ABCD的边长为2,∠A=60°,以点B为圆心的圆与AD、DC相切,与AB、CB的延长线分别相交于点E、F,则图中阴影部分的面积为( )
人的精子内染色体的组成,可以表示为:( )