植物中（尤其谷类、豆类）的P主要以植酸形式存在。
参考答案：对
植树活动中，小华种了a棵树苗，有b棵没有成活，这批树苗的成活率是______%．
All the bees had been at nearby feeding place were doing the circling dance.
A．which
B．what
C．that
D．how
