Please remain _________ until the plane has come to a complete stop.

A．to seat

B．to be seated

C．seating

D．seated

Reidel叶是一种正常肝脏变异，其定义是()

A．肝左叶的伸长

B．尾状叶的舌状伸长

C．肝右叶的舌状伸长

D．肝左外叶的舌状伸长

E．肝方叶的舌状伸长