生态系统的物质循环是指组成生物体的物质在 _______与________之间的往返循环。
生物 无机环境
—Is your school bigger than ours?
—Yes. I guess it is________your school.
A．as twice the size of
B．as two thirds big as
C．bigger than half
D．one third bigger than
根据五行相克规律，水的“所胜”之行为
A．土
B．金
C．火
D．木
E．以上均非
