读一读，给下列句子排序。

A. Then we put Christmas things on the tree.

B. It's fun to put up a Christmas tree.

C. Finally we put our gifts under the tree.

D. Next we put the star on top of the tree.

E. First, we put on the lights.

F. It's beautiful.

G. There! It's done.

正确的顺序为: B  ____________________________________

下列左图为水稻幼苗根尖结构，右图表示营养液中氧含量化对黄桷树幼苗吸收K⁺速率的影响。请分析并回答下列问题：

黄桷树幼苗根细胞吸收K⁺的方式是（），主要部位是左图中（）区。