A:was seen beg
B:were seen beg
C:were seen begging
D:was seen begging
△ABC中,∠BAC=90°,AB=AC,点D为直线BC上一动点(点D不与B,C重合),以AD为边在AD右侧作正方形ADEF,连接CF.
一共有____ 根香蕉。
下列关于生物生殖发育的描述中,错误的是( )