一般苗木长至（）高以后，应逐渐去除遮阴物。
A、2~3cm
B、3~5cm
C、5~8cm
D、5~10cm
参考答案：D
After school he didn't go home. ______, he went to the playground.
A．But
B．While
C．Instead
D．Instead of
养鸡的四大技术支柱是什么？
